Alves can succeed in the right type of system with good support. As long as his defensive duties consist of hard pressing all over the pitch and basically being the 2nd pressing man in most defensive situations, he can fulfill the role very well. Juve played with a back 3 against Monaco for both legs with support from Pjanic/Dybala/etc. in defending. Even when they play a back 4 with Alves at RB, he has Cuadrado/Pjanic/etc. in support with a perfect CB combo behind. That, plus their constant and safe organization in defense, means that Alves can actually be a positive and great defensive player without getting exposed like he was when Barca's defense crumbled after Tito got ill and then further when Tata was coach.
Alves is still a GOAT right back with the right support and can play at a very good level when his shortcomings are masked. The same will likely hold true for Messi for years, if he can be supported properly.