Well kinda and kinda not. The reason he has no wins with the best car is because there's also Verstappen with the best car beating him. Realistically he's only had 2 chances to actually win a race, one in Singapore (but there RB really messed up with the config) and last race because Max retired.
I think that's just testament to how dominant Max has been. The last win Perez got is the one that he snuck in and he hasn't beaten Max since then (last race not counting).