FWIW, the biggest sporting event of all as far as total number of world's eyeballs and endless news cycles...is either the Olympics or the World Cup...take your pick. Who knows which stripe of terrorist will decide this is their stage for maximum havoc. Who knows what and which protestors or terrorist groups could cause someone's death. This is what I call nit-picking and obfuscation.
Furthermore, a boycott will not affect Russian policy and sway Putin one iota. Just athletes handling it in a more subtle but different way with armbands and speeches will elevate the Russian mistreatment and spread the word to portions of the world that might not know about it, as admittedly ineffective as that act would be. However a boycott would not yield any useful Russian policy change. they don't respond to outside pressure regarding the internal domestic national politics.
Bottom line is their is a civil war in the Ukraine and there is going on now an even bigger world stage being given with questionable safety and security.