Adding to this,
i have tested the same seed (1404998407) with experimental toggle on and off, there should be a Zombie dungeon at
524 54 230
and it is there with the toggle off, turn it on and no dungeon, i have also used an xray texture pack and there are no dungeons in the 2000 x 2000 area i covered, except for the stronghold silverfish one and cave spider ones in mineshafts.
This has not been resolved, in the 1.17.10 update (experimental toggle on) this is still happening,
to recreate spawn a snow golem, and no snow trail is produced.
To clarify and to add i have tried on screen keyboard, usb keyboard and chat pad (all on xbox series x) none of them allow any input, except the chatpad delete worked and now i have no world name.