Not sure if you knew, but Yakuake is very similar to tilde from what I've heard and has worked flawlessly for me on Wayland.
https://apps.kde.org/yakuake/

What are they moving to?

Same boat for me, supposedly they are moving away from FACEIT though according to a recent dev chat (apologies for the reddit link if people care- https://www.reddit.com/r/SteamDeck/comments/14v3sgb/in_a_recent_weekly_recap_with_the_battlebit_devs/)