MTG Salvation

For example is a bear nornally considered on the same level as a bear IRL? As in very powerful and very tough?

As far as we're aware?
I mean, there have been very few bear appearances in the lore, but they seem to be treated about as you would expect a bear to be treated.

4 Little Girls can kill one so... maybe?

4 Little Girls can kill one, but they'll all die too.

Combat between multiple creatures doesn't cover the lore very well. p/t is made sort like a power ranking scale. A 2/2 creature is stronger then a 1/1 one, but how much stronger it is not covered.

If we wanted the game to work realistically it would have to have more divisible scale. Like, we would need 24/21 bears and a much higher starting life point. Also, spells that summons 1/1 creatures always need to summon dozen of then.