I do agree with your underlying defense of private property. Spotify has a legal right to do this. There is no contractural issue here. And this is not censorship.
But there is a cultural question that I think this defense sidesteps a bit. I'd frame it as a question.
What level of heterodox opinion would you encourage Spotify (and the like) to tolerate? What opinion would be heterodox to you or your peers that you'd want to see Spotify to defend as the realm of reasonable on a platform of broad interest to the general public?
Not sure whether your question was rhetorical but here is a suggestion anyway:
Draw the line where people spread lies or harass others so that actual harm gets done in the real world. Alex Jones got deplatformed after some of his fans were threatening grieving Sand Hooks families. Joe Rogans episodes were removed after they spread misinformation that convinces people to not get vaccinated in the middle of a pandemic, which will probably cause some deaths given how many people listen to his content.
This sounds good at first, but I think it wears differently if you try to apply it to something in a different political quadrant.
Consider in the summer of 2020 there was a popular social movement that had quite a presence on social media that was spreading incorrect and ultimately very harmful statistics about police violence.
Arguably, this led to wide spread riots, large scale property destruction in multiple cities and ultimately an increase in crime. I think if a vocal minority bullied large corporations to effectively deplatform those social justice organizations then I think many people would be playing a different tune.
Lol. Why is the Dr.Mallone and Dr.Peter McCullough interview still there? Those are the controversial ones. They did not say not take the vaccines. Dr.Mallone said that he is vaccinated.
But there is a cultural question that I think this defense sidesteps a bit. I'd frame it as a question.
What level of heterodox opinion would you encourage Spotify (and the like) to tolerate? What opinion would be heterodox to you or your peers that you'd want to see Spotify to defend as the realm of reasonable on a platform of broad interest to the general public?