Getting De Gea back is still a terrible idea, and I have said this probably a month ago when the rumours first started and saying it again. He is old, he is getting to be 34 or something, maybe more, makes no sense to hire someone who is that old.
Of course he would be much better than Onana, nobody questions that, but if you are a true United fan, you would remember his last year, his reflexes wasn't enough and he was having trouble. He worked hard on the season he didn't play, but then he got into Fiorentina and showed his hard work, but how long will that last? One more season? Two more seasons? I doubt he would do good for a long time, we are not going to see him do much all together, we need to remember that, they need someone younger.
I don’t see the need to bring De Gea back to Manchester United. The decision to part ways has already been made, United have to move on. If Onana is no longer m good enough for the team they can sort other options elsewhere, I believe De Gea is not the only good keeper available to Manchester United.
United needs to accept the fact that De Gea has moved on with his life and let him be. I believe we still have brilliant and young goalkeepers out there who can do better than De Gea. This is the problem that United is having, instead of searching and looking for good players and goalkeeper for replacement of the old ones, they will be looking for players/goalkeeper that will not be in their peak form for long. De Gea is getting old.