I wish such an effective labor head could have worked for the average American worker instead of the MLBPA. What he and Gene Orza did was treat player performance enhancing drug use as a just another bargaining chip when negotiating CBAs with the owners, instead of acknowledging that it was an issue that hurt both union members who never used steroids or hgh, as well as the long term health of union members who did do these drugs.
Baseball remains fairly popular but probably runs second only to English Premier League soccer when it comes to being a plutocracy. He shares a lot of the blame in the fact that every free agent period and trading deadline inevitably results in a team from New York, Boston, Chicago or LA ending up with the top talent by the mere fact that smaller teams can't compete.
One of his contemporary player association heads, Gene Upshaw of the NFLPA, was a prime example of a negotiator who failed his members in bargaining, retired players' welfare and looking out for their well-being when it came to concussions and long term brain damage, so I suppose Fehr could have been a worse union head. But then again, the NFL is the most popular league in America, and its players have prospered as much as anyone. So maybe relative labor ineptitude paired with team owners practicing socialism is exactly what a sports league needs to be successful. Donald Fehr was just too good at his own job, and in my opinion hurt the game more than he helped it.