I've recently heard people talk about "modularization" for the third time.

Honestly, the biggest changes for someone like me, a end-user, might just be two points:
Transfers/interactions become cheaper and faster, and with more chains, the experience becomes more fragmented...
Having a bunch of networks in my wallet, switching back and forth, bridging back and forth, and occasionally worrying about issues with bridges and sequencers.
The upside is that I can try more with the same amount of money, and the downside is that it's easier to slip up.
As for re-staking and the "compound yield" of shared security, it really sounds like a nested doll, and I haven't quite figured out who bears the risk.
Anyway, I'm still the same old me—placing limit orders slowly, keeping an eye on key levels, and not getting swept up by flashy yields.