I think it's ok to condemn the action and say that, regardless of where he comes from and what the conditions are on average, he is a human with higher-level thinking abilities at the end of the day and does know that beating a defenceless loved one until she's bloody is wrong. However, that doesn't mean that taking into consideration factors that help explain the commission of the act = condoning the act. There's a difference between an excuse and an explanation.
None of us is around the day-to-day operations of the Blue Jays and none of us knows Roberto Osuna personally. We will never know the level of contrition that he has shown or will show, and further, we don't even know the details of the incident right now (let's assume he's guilty for the purpose of this post). We're a society that believes in redemption and rehabilitation. Osuna is going to pitch elsewhere again. We could take a moral stand and trade him for pennies on the dollar, but for what? Do we have a higher moral duty than the acquiring team to keep him off our roster? And where does it go from there, do we immediately release/trade any player in the system who commits a crime? The roster move would just be for show otherwise.
I'd say the Jays have the duty to ensure Roberto is provided with all of the resources he needs to successfully rehabilitate. If he doesn't show the requisite contrition and commitment to rehabilitation, then that's a different matter and perhaps he should be moved. Because, for one reason, he becomes a liability.
I've also heard the argument that someone who commits a violent crime should relinquish the privilege of playing as a professional athlete, and enjoying the luxuries that come from such a job. That means the person can still be rehabilitated but isn't kept from earning a living. I can see the logic in this and even agree with it on some level, as I too of course find that act reprehensible. But there are two problems: 1) MLB will never approve such a policy, meaning the original team will be standing on that hill alone. 2) That's a form of vigilante justice and I'm not fully comfortable with the moral implications of that either. When we put our trust in the justice system, we relinquish our ability to mete out our own justice.