His fitness is unreliable I agree but you can't solve the problem without big money and that can only come by selling Dybala and someone like De Ligt if people here want a Haaland or De Bruyne problem solver. Short-term and cheap options like Insigne and Mertens are attainable but even then, they wouldn't be that cheap given that we didn't want to pay too much for Scamacca.
If Juve wants an upgrade, it'll cost a lot is all I'm arguing. For me, the team would benefit more with a new LB, LW and creative midfielder than Vlahovic because I'd expect the levels of Kean, Kulusevski and Kaio (KKK lol) to develop more and that seems like better economics to me. It would mean that we also rely less on Dybala and maybe we can rest him more.