Bolt 12 does away with the need for using domains and not having to rely on a web server. I guess someone could map an address to an existing Bolt 12 invoice in a similar fashion to how a Bolt 11 LNURL is mapped to one. Someone smarter than me should answer though.
Discussion
Yes that's what I assume, the same way an lnaddress returns an invoice you can setup to always return the bolt12, should be easier since it's a static code, but it's not retro compatible, wallets that don't support bolt12 will ask for an invoice and won't know how to handle it.