Bitcoin layer 2s are not bitcoin and even the more let's say promoted solutions like the one programmed by Adam Back are flawed in their design.

There's a centralised point of entry and exit for BTC in and out of this system and the issue remains that this ends up being trust based along with all the problems of centralisation.

How independent could a layer 2 remain if the programmers on the payroll for it were arrested and the company developing it disbanded?

We've seen in Coinbase's later 2 as well as in solana chain transactions were halted for extended periods of time until a fix was issued.
These situations are not pleasant and hint to extensive centralisation in these systems.

The most independent form of scaling for BTC is on-chain. Currently with segwit blocks there can be maybe 7 thousand transactions in a block every 10 minutes? Well, surely it's not fast enough to verify a transaction at this pace for everyday needs and also not enough capacity.

Hardware and network infrastructure had improved since this debate was happening last time, so perhaps it's time to start discussing on-chain scaling again.