Iām not sure this is a good idea. An L2 may change or may go away at some point in the future. Being able to move a .eth domain back to L1 should always be an option, even if this means that any other information that was stored in the L2 resolver will be gone.
The challenge with this is: if we want to deal with the possibility that some L2 will go away, then who decides whether or not a migration happens? I guess one option would be to allow individual names in the L2 to withdraw to L1? Ideally we could even package many names from the same L2 up into some kind of NFT with a Merkle root, withdraw and move that token to a different L2, and then unpack them in the destination L2.
Would either of those paths be possible within the context of the existing ENS standard?