If you were smart, anticipating the dystopian near future you'd put all your effort in making Monero as easily available as it gets.
Seems Bisq dev are neither smart NIR do they have a sense for where society is heading in the near future.
Discussion
My understanding is the roadmap is not set in stone and if a dev joins who wants to work on XMR atomic swaps then it will get implemented sooner.
As it stands the current devs involved in the project don't have much familiarity with XMR Atomic Swaps, hence it appears last on the roadmap.