I agree with this.
I said the same with Sanchez last season: don't want him.
Imo, if we had signed Sanchez at the start of last season, Sane would not now be y.p.o.t.y. & Sterling would have considerably fewer goals due to both having far less responsibility.
No guarantee Sergio would have found the form he did, either. (It might even have fucked up our season, when you look at how average Sanchez has been for both Utd & Arsenal). I think he would have just been a huge spanner in the works of our forward line. Hazard hasn't been much better than Sanchez apart from a few flat track bully performances.
Hazard is a huge level above Sanchez though, & for that reason, makes it potentially much worse for all of our front line imo. As you say: he has to play. Someone has to drop out, most games & if he isn't actually as good as the players we already have, when he does play (which is a 50/50 possibility) & does get less time than he anticipated, he will stink the fucking place out with attitude & try to drive a wedge between the manager & KDB etc .
If we sign him & it works out, we will possibly be even better than we are now, because he is one of the best, individually. If it doesn't work, it will probably cause some of the current team or manager to leave.
We don't need him, we can still improve hugely without him, by signing alternative competition for places, without needing them to have superstar status. So why risk it, at his age ?
As it happens, I don't believe for one second that we will try especially hard to sign him, for the reason that we don't need him. I recon we'll enquire, laugh at the fee & that's it.