Previously i was using Chromecast with Google TV, it has My5 and ITV Hub, still annoying no All4.
I bought my new OLED 2021 Sony TV with Google TV, i tried to find ITV Hub in the Play Store and its missing. Very dissapointing.
UPDATE: as of 25 December 2021 firmware, Sony brings all the on demand services including all 4 and itv hub
All 4 doesn't support Android TV.
What do you mean by "fails to go to main screen"? It doesn't get installed, or it doesn't open after installing?
A workaround would be casting from your phone to the TV.