I think reducing subscriptions is fine. But I also feel paying a sub for something that has value and has an ongoing cost to run/maintain is not a bad thing, so long as it respects your privacy.
Paying for Netflix: bad. You should be able to purchase the shows and films you want to watch rather than subscribe. There’s very little ongoing cost associated with providing DRM-free downloads, if they wanted to.
Paying for email: fine. It’s an ongoing cost to run and I also think it’s mission critical enough that you need reliability and robustness, so I wouldn’t self-host either.