It kind of depends where you start from I guess. As I understand it, Tuchel had a huge advantage in that Lampard was already coaching high press, albeit not very well. We have a number of very highly paid players who look like they would be terrible at playing a Genenpress. Ronaldo, Maguire, De Gea, Pogba to pick the most obvious ones. So we have a lot more work to do. And getting players of that quality who can also press is a lot harder than getting mid table players. Are the Glazers likely to fund this? Did they realise a load of squad surgery would be necessary when bringing in Ralf? I doubt it.
Maybe I'm wrong and Ronaldo and De Gea will transform their games. But I don't think so.
On spending the Glazers have yet to not sanction big spending, I think this summer will be no different. I also think RR would have been very upfront about his thoughts on the squad. Gegenpressing has been going on for yonks, it's only because it's United we're now getting bombarded with pundits talking about pressing and who can and who can't, truth is how many of them have even played in a pressing system? My expectation is there will be some games where we simply don't have the personnel: City, Pool, Chelsea being the obvious three and we might look a bit crap in those/revert to a defensive and boring performance but otherwise I would expect by summer that our pressing stats are significantly up.
Yes, I do think some players are going to struggle, Maguire, AWB unless he picks up form, Ronaldo but the bulk of our team I think is very well suited. Henderson, Shaw, Dalot, Lindelof, Bailly, Fred, McT, Donny, Bruno, Sancho, Rashford, Greenwood are all technical and/or physical enough to be successful. Are they going to all be world class, of course not but surely we should be able to impose ourselves on 70%+ teams in the PL once the system is in place (not saying we'll win all those games but we'll see the press).