looks like @ZachBacon is currently building gnome 42, so perhaps we can expect it this friday, or maybe it will require extra testing and will arrive a week or 2 later perhaps
ive been trying it out on another distro, looks like everything is working fine there, most extensions as well.
as for libadwaita seems there is a way around it, just copy the content of your favourite theme's gtk-4.0 folder to ~/.config/gtk-4.0 and your gtk4 apps will take on the looks of your theme, unless the app developer has specifically blocked using non libadwaita themes. none of the apps made by gnome has blocked this as far as i can tell. so maybe it wont be too bad