You're making a lot of assumptions about what you 'need' to do to keep up with the rest of the table. If your meta is indeed hyper-competitive, with everyone building the absolute best deck possible then you're right, but that's what magic is like, as most eternal formats congregate to a limited number of best decks.
However, not all meta's are like that. For example, in my local meta I wouldn't need to ru anywhere near that amount of mana acceleration, and 6 mass removal spells is decidedly overkill. We barely run any tutors in my Meta and I in particularly avoid playing tutors unless it does something particularly interesting (such as congregation at dawn in Gishath, or some non-basic land tutors in sisters of stone death because that deck really needs the massive amounts of mana to function).
All of this is to say that interesting deck building does not have to be dead. If your group values that aspect of EDH, all they have to do is agree on some global limits to their meta to avoid playing cEDH.
However, not all meta's are like that. For example, in my local meta I wouldn't need to ru anywhere near that amount of mana acceleration, and 6 mass removal spells is decidedly overkill. We barely run any tutors in my Meta and I in particularly avoid playing tutors unless it does something particularly interesting (such as congregation at dawn in Gishath, or some non-basic land tutors in sisters of stone death because that deck really needs the massive amounts of mana to function).
All of this is to say that interesting deck building does not have to be dead. If your group values that aspect of EDH, all they have to do is agree on some global limits to their meta to avoid playing cEDH.