There are actually a lot of physical cards that help with this. Anything that forces player's creatures to attack each combat might help. Anything that can accelerate mana ramp could also in turn build people up faster so they can have earlier, more explosive plays.
Aside from things like that, maybe talk it over with your group and get more aggressive decks in the mix.
There's a couple reasons this could happen I guess: Durdling
Personally I find this is something you can help with a little social lubrication. It becomes a little 'nudge nudge wink wink' but people get the gist. Encouraging people to engage in threat assessment helps them get better but also helps make them decide what they're doing quicker. Eventually someone has to sack up and attack someone else, so stir the pot or get others to do it for you. My guess is this is the reason your games are taking so long. Encourage bravery and daring plays, hand out compliments for people taking risks and get people to interact. No one wins if everyone just sits guarding their fort. Tutoring
There's not much to say here that hasn't been said before. A lot of time can be saved if people make this part of the game efficient; cast the spell, if it doesn't imapct any of your further plays find your stuff at end of turn. If it does you clearly know what you're looking for so find it quick. Combo and Jank
It's probably pretty unlikely that combo games last this long. Janky interactions that mess with the table, well...if they're not going anywhere just tell the guy doing it to sort themselves out and hurry it up. Stax
If it's taking this long and you're not enjoying it, tell the people playing stax to choose another deck. It's not the worst thing in the world, even if it's a 'love it or hate it' way to play, but if the games are that intolerable say something.
My group plays a house rule where the game ends when one/two player is dead (depending on the number of players and board state). This creates much faster games since everyone is less likely to play defensively.
The advantage of this rule is that a five to six player game usually lasts only 1 hour. However, the downside to this is that it really affects your playstyle and deck building in the long run.
Jam a combo (or immediate wincon, at least) in every deck, is my policy, and plenty of other players I know do the same.
It doesn’t have to be an easy or simple combo or wincon. And tutors should be included minimally, if at all, assuming you want ‘casual’ play at all.
Otherwise, yeah, what you described in the OP is what generally happens.
edit: The flipside, of course, is that all players - or most, perhaps - will want to have some relevant disruption available to them, in case some combo/wincon randomly comes up real early. But hey, quality disruption is always nice to have, so...
Talking with them may help to find out if anyone else has an issue with this but if you want something done you'll most likely have to do it yourself. You could make your deck more "competitive" or you could just start attacking when the opportunity arises. If it doesn't feel right don't do it as I assume you still want to have some fun here.
Me and a friend of mine tried to find a way to speed up EDH / Commander games by building 60 card singleton decks similar to Brawl except all cards are Vintage legal while also following the Official Banlist by the EDH Rules Committee. Unfortunately we rarely ever get to play the decks since we usually do traditional EDH / Commander with 100 card singleton decks since my friend's been enjoying Shu Yun, the Silent Tempest more than Yuriko, the Tiger's Shadow where it takes awhile to get her going.
We recently came to the conclusion that there's some Commander strategies that won't work in 60 card singleton such as decks that are able to run numerous copies of one card with Shadowborn Apostle hence why Athreos, God of Passage is 100 card singleton since he wouldn't work in 60 card singleton. In the case with Shu Yun, the Silent Tempest it was about maximizing instant and sorcery cantrip spells to take full advantage of his Prowess trigger while giving him double strike to help one shot opponents.
My playgroup had a discussion about people being wussies about attacking and we all agreed collectively to stop throwing fits when we get attacked. It helped a lot.
I kinda started the parade by making an aggro deck that was always attacking (Skullbriar).
So that's one way you can kind of use soft communication--make a deck that focuses on dealing combat damage to trigger and explain that you need to be attacking to make your deck tick. perhaps Alesha, who smiles at death or something.
One guy had Mogis, God of Slaughter and shortly thereafter dropping him, proceeded to drop Havoc Festival. Despite the fact that all other three players had colors to deal with the enchantment, it stuck around until everyone was in single-digits life.
Edric, Spymaster of Trest. If everyone is holding back and not attacking, you can give them a reason to attack. (Generally attacking the Edric player is the correct play, but I suspect players that are used to sitting around not attacking won't think like that.) Include a bunch of cheap evasive creatures so that you have profitable attacks even when your friends are holding up blockers.
Whenever i drop any of those cards, the game just ends soon after. I don't necessarily win, but it really pushes the game forwards.. the table normally stops durdling about and really get their act together at that point. 'tis good fun!
You could also tune your decks to have a lower CMC (not necessarily raise the power level though), and do more things on your turn; disrupt your opponent's big flashy things. it'd put more pressure on them, and they're gonna have to play your game rather than you play their durdle-game.
This is one of the places where I think stupid combos might have their place. If they don't do anything to end you, I think you should punish them for it. Or play a red/blue deck that forces attacks while protecting yourself, maybe.
I would say people need to own their decks. By that I mean that if someone wants to kill with creature damage, then they should own that and be aggressive. If they go for combo, add more tutor and draw to aggressively find that.
And honestly, add more removal. That sounds weird, but knowing that my friend runs 14 removal spells means I’m trying to win faster so I don’t risk losing my threats. I have to act ASAP because my threat could get removed if I Durdle or am afraid of attacking.
Beyond that, I recommend playing Krenko. Games will end real fast.