That's an interesting theory and way of thinking...
Withdrawing to L2 self-custody will take the place of full self-custody for many, and those selling will be able to sell their Bitcoin representations as easily as real Bitcoin.
We can see this happening at these moments... Personally, I didn't "bridge" BTC to another network, but I did my ETH, for very similar reasons that you described... It is happening, and it looks like the biggest "disadvantage" of BTC could actually save it!
Yeah let's hope.