From a neutral perspective, I don't really understand what the hold-up would be on Salah's extension--I suppose its just length and FSG not wanting to have too many years of poor Salah performance?
It's clear that Salah is still playing at a very high level, and it's also clear that Liverpool is reliant on him and his sensational quality and consistency to compete. Liverpool have a squad right now that is capable of winning every competition--multiple trophies over the next few years. You've got to pull the trigger on satisfying your talisman, even if he is 32. He's a legendary player that the fans love--I think fans are savvy enough to understand that maybe in two or three years Salah's on way too high wages for his production level, but it was worth paying him the extension because the team was going all in and Mo has earned it.
Also---if he ends up being on too high wages in a year or two--can't you just sell him off to the Saudis?