We're overdue a proper new 3D Mario game. The 4 hour remaster bolt-on doesn't count.
Odyssey was something like 11 months reveal-ship. They could announce Odyssey 2 out of nowhere soon and it can still ship this year. Kinda surprise they haven't already honestly, literally just create 18 more kingdoms and it's a job done.
Do I think it'll actually happen? Maybe not.