Stirling makes racist comments in a private conversation and is banned for life from the NBA.
Vick fights, abuses, tortures, kills dogs and is welcomed back into the NFL.
Who is worse?
Sterling's actions with regards to the housing situation is pretty low; but I've got a soft spot for dogs so I definitely feel like Vick's ACTIONS were worse.
That said, it's a stupid question to ask as it relates to you pointing out their stance with their respective leagues.
Sterling was an owner of a franchise; a position with significant impact to the league. His actions were set to cause the league significant financial damage in the way of lost sponsors, potential legal ramifications of games being cancelled (multiple players were reportedly going to boycott playoff games had the league not acted strongly), and an absolutely toxic franchise (multiple free agents, including their coach, and even members on the team made it clear they would not play for the team if he was there).
Thus, the NBA made a business decision. There was no fathomable way for them not to take a significant and problematic financial and logistical hit without removing the owner.
When it comes to Vick, despite his popularity before hand was still essentially just a game piece upon the NFL's board and one that could be discarded without much of an issue. The actions of a single player, on a single team, is unlikely to warrant the same type of significant public and personnel outrage that an owner will because a single player simply doesn't have the same level of impact and control.
Additionally, the NFL was aided by the fact that Vick was undoubtably going to jail. This allowed them to easily wait a significant period of time before actually making a decision. As the phrase says, time heals all wounds. The fervency towards Vick as he was close to being out of Jail was FAR less than it was right at the start. Additionally, the act of actually going to jail create an already established "punishment" for what Vick did, lessoning the feeling that the NFL would necessarily need to significantly act to "punish" him for his actions.
Finally, when it comes to the NFL, this was not an uncommon situation in a general sense. Players had previously had run-in's with the law and were allowed back in then NFL.
So whether or not anyone
personally feels the actions of one or another is worse, that's somewhat irrelevant as to whether or not it was justified for each league to act in the way they did.
Especially considering the most obvious option...you're comparing two different leagues with two different decision makers and expecting them to have some kind of similar action simply because they're both sports.