not sure thats true.
Even if they go down, its likely enough of their transfers will have been a success, to allow them to have a huge headstart in terms of quality to get promoted again.
There are some players they have signed (or already in the squad), who have proved they are at least top level Champ players.
I actually like quite a few of their signings:
Toffolo - left back who was high quality in the champ.
O'Brien : midfielder who was high quality in the champ, really silky and hard working midfielder.
Gibbs - White : was touted as one of the best performers in the Champ last season, 25m base fee isnt a million miles off the going rate for the best performing Champ players over the last few years (even if the expected add ons to 35m are true, if he performs that still isnt a million miles off the going rate for top end Champ performers coming to a PL team), if they go down, he will be a force for them next season.
Richards - left back from Bayern, was highly touted a couple of years ago.
Dennis - did fairly well in the PL last season, certainly top level Champ quality at minimum, almost certainly mid/lower PL quality.
Neco Williams - right back, looks a decent signing imo, if he isnt PL quality, he is certainly a top Champ level player.
Kouyate - probably a decent, proven backup midfielder at lower end PL level.
Henderson - clearly a PL level keeper.
Lingard - yeah a lot of salary, but its a 1 year deal, so nothing lost if it doesnt work out.
They have taken some chances on players like Awonyi, Mangala, Biancone, Niakhate & Freuler, but its likely at least some of those will prove decent signings.
I think overall, they are having a really good window, i also think they have a good chance of staying up.
Even if they dont stay up, i think there is enough quality there now to come straight back up.
to be brutally honest, i think their business is better than our promotion year, ofc thats yet to be proven, but i think it is on paper.
I think they will stay up.