I detest it, I really have an issue with fighters constantly high fiving and fist bumping and even sometimes hugging during the fight, its ridiculous and is a huge disgrace to the history of the sport and everyone who has ever competed in it
If you notice basically all the fights where the 2 fighters are constantly high fiving and fist bumping never end in a finish, it always goes to decision. I think thats because it just gives the vibe of a friendly spar and the fighters relax more.. even if they don't want too, its subconscious.
As you said fist bump, high five before and after the fight is great and thats respect, no issues whatsoever. But to keep doing it during the fight just gives the impression its not a actual "fight" and all seems too much like friendly sparring to me.. and like I said why is there no finishes in those fights. Just by the law of averages theres probably a fight where there was a finish when the fighters were constantly high fiving and fist bumping after a flush punch was landed... but honestly most of them go to decision, I've noticed it since ages