I think it was more of an artistic choice that it would’ve been weird for the entire Series Finale to culminate in Ted leaving to go back to America only to show him right back in England 20 seconds later in another scene.
Like, yes, we know time will have passed, he can always come back when he feels like it, but I do feel like if they showed him right back in the UK it would’ve undercut some of the gravitas of him leaving.
In the God of War series Kratos dies and then climbs his way out of Hades
Twice
Three times even, but the first time is late in the game