What is this layer 2 you speak of?
EVM clones?
That's actually not layer 2.
Those are just different networks/tokens.
I have seen zero layer 2 implementations.
Perhaps you have a better example.
As far as I know they've been stuck transitioning to proof of stake this entire time.

But you're not wrong, Hive has already done this.
A good example was Splinterlands taking operations off chain.
The next Hive Hardfork is going to make second-layer apps much easier to create.
Hive is way ahead of the game.