Can you imagine if the Cardinals outbreak was traced back to Jon Jay? The place would melt.
You make some fine points.
I do think it's natural to want to know who to blame when something like this happens.
I get that.
But with what we know about the virus, and the system MLB is trying to operate, it's impossible for me to ignore all of the entry points that exist for the virus to sideline a team.
Yes, it's easy to pile on if Player X did something shortsighted like go to a party. But the virus could have just as well met Player Z because his wife went to a book club gathering and brought it home. Or Coach T caught it from a teenage child. Or something else.
Baseball is trying to play through a pandemic while sending players all over the country and letting them go in between their homes and the ballpark during home games. The virus is going to get in. It happened faster than anyone thought -- and now the goal is to tighten protocols to do a better job of keeping it out, and to make sure it has less of a chance of spreading between teammates once it gets in.
Whether you take the virus seriously or not, it's clear that America has not done a great job of slowing/stopping the spread.
So I'm not sure, realistically, how anyone expects baseball teams to do that under these conditions.