I'm very curious, especially after Adam Back mentioned "trade-offs" of using Lightning, or Liquid. I believe using Drivechains might also just be a matter of accepting the trade-offs.
https://twitter.com/adam3us/status/1217845788438601733lightning makes security tradeoffs, liquid makes different security tradeoffs
These are two very different situations.
Lightning and Liquid can be thought of as off-chain or out-of-band. They have no effect on Bitcoin's consensus. The security trade-offs -- like needing to keep private keys online in LN, or trusting Liquid validators not to steal funds -- only affect LN users or Liquid users, respectively. Bitcoin users are unaffected no matter what.
With drivechains, Bitcoin users can't opt out. That's the difference. Drivechains are soft forked into the consensus by miners.
With consensus reached, what would be bad about that? Segwit was soft forked into consensus with the backing of full nodes behnd it.