To the extent that stunt fights like Mayweather / McGregor - and subsequent fights like Ngannou v anybody - go on a boxer's legitimate record it becomes problematic. Mayweather absolutely includes McGregor on his "perfect" official record. Which is bull****.
Back in the day, when an exhibition got made - and there were plenty, the sport's always had them - it stayed an exhibition. Ali's exhibition vs Inoki isn't part of his official record.
The other problem is how these social media fights crowd out money and interest from the real thing. We've seen Showtime and HBO abandon boxing - some of which is attributable to the struggles of new streaming business models, some of which is the intrusion of competitors like MMA and the atomization of the combat sports audience - and we're seeing legitimate fighters (ie, Joshua, Fury et al) more and more making these stunt fights instead of fighting real contenders.
The market decides certainly, but the circus bout eventually corrupts and crowds out the real thing.