sometimes it's a matter of means & availability, sometimes it's a matter of controlling their paid-for content (like people who actually buy switch games but want to run them on their steam deck), and sometimes it's basically a hobby

Very little of that justifies it to me. For means & availability, this isn't a mother stealing baby formula. Pirated content isn't a need (though I'd make an exception for things like school books). There's plenty of content made to be free and available, as well as libraries. And I'm completely fine with people pirating copies of paid-for content; there's an argument to be made that that isn't actually piracy and is personal archiving. It probably doesn't need to be said that "hobby" is not a justification in the least, just like people who shoplift for the thrill.

I see supporting a service hostile to users as immoral - it's like enabling an abuser, however slight, you're contributing to behaviors that are a detriment to others

To me the real crux is that you believe that not doing something immoral is the same thing as doing something moral. Me sitting here is moral because I'm not murdering someone. Yay me. I'm also not blackmailing, gaslighting, stealing, etc. etc. Me sitting here might be the most moral thing anyone has ever done.

To me the case for the absence of activity actually being moral is it requires some amount of sacrifice to continue to do the right thing. Avoiding going to Walmart to support a local business, even if you pay more and it's further away. The difference between not wanting to see a movie and boycotting it. There's nothing moral about not going to a movie you didn't want to see. But I think it is moral to avoid going to a movie you wanted to because of labor practices; you made a sacrifice in support of your beliefs. If you then go and pirate said movie, it's indistinguishable from selfish behavior.

As I've said in other spots, if it's genuinely about not supporting hostile services and not about self-interest, donate however much you're saving by pirating to a union or charity. That's completely fair. But if not, all I see is people acting in their self interest and trying to justify it by saying that they are doing a bad thing to bad people so it's okay (and maybe they're doing a little bad to some good people as well, but that's a price you're willing to have them pay for you).