Actually, he didn't sell our best players.
Since he took over, his strategy has been rather conservative. Under the previous management, we worked more or less like Leipzig. With good results - Champions League semifinal, second and third places in Serie A - until Monchi was hired as DoF. Yes, the guy who's now in charge of Aston Villa. He's been awful for us. In 2 years he got all the transfers wrong while making massive debt. Our strategy was completely based on value rise "buy low sell high", but in just 2 years of bad management it was over.
Friedkin has tried to do something very different, bringing Dybala and Lukaku. Yes, Mourinho was overall a bad choice. It wasn't going to work with FFP rules to comply with. Yet somehow it partially worked in Europe. Now they have announced they'll focus on young players to develop and have changed DoF again. The fact is, Friedkin has money and respect for European football but... he's still from the US.
He obviously lacks proper understanding of the game. He's learning by trial and error. Nobody would have hired Mourinho with a team to rebuild. Mourinho is someone you call when the team is ready to win. But I can say...the apprenticeship has not been so bad for us. We see potential.
Outside the pitch...only good things. Commercial revenue has gone up, he has revamped the stadium project by changing location...
And to be fair he won a European trophy and reached a UEL final and 2 semifinals while...moving in the wrong direction. We're all wondering what he can do when he finally goes the right way. And we hope with De Rossi he'll start soon.