I have lots of these guys around me.
If you want to trigger them, just tell them that their best player at the moment is some guy who was just a rotation player for a 17th placed Udinese and a midtable Sampdoria. It hits the nail and they make up wild "excuses" of how he was shit back then and now he's developed into a great player
Honestly, it's still the same guy, there wasn't much improvement since his days at Udinese. He always was very technical with a great pass and shot but he was quite soft. De Paul for example has been 2 tiers ahead of him and he's not even a top player.
These guys will overhype garbage just because that's how they're used to. From Phil & Gary Neville to Darren Fletcher, John O'Shea, Wes Brown etc. Their recent players get hyped on a weekly basis and there are many mood swings. Several seasons ago at various points Rashford was the next Luis Suarez, Lingard was the next best thing, Welbeck was a prodigy. It's one thing to respect their tendency to promote their own talent but these guys are taking it to another level pretending that everyone of them will become a Giggs, Scholes or Beckham.
But it's not just Manchester United fans. These guys are just more and they're mostly the window of PL fan bases. They're almost all alike in that regard. Mbappe mocking them with his tweet about "farmer's league" was too funny to witness