noone else could save it from being cancelled after 2-3 years after Lorne leaves and I think he knows that. The question is, does Tina want to take on that milestone and risk being the one that sank a 50 year old TV institution?
I think whoever takes over has to time it such that they do it officially essentially the day he dies, and then build out “The Final Season” as a tribute to Lorne before shutting it down on purpose.
Like, Fey agrees to stand at the helm of the ship on its last voyage. Not trying to save it, but to give it a good sendoff kind of vibe.
Anything else, and yeah, like you say, it becomes an albatross around whoever’s neck is foolish enough to take the job.