Now developers have to give their source code for free and can also not monetize subscription. Is it some kind of modern slavery?

The only place I'm insistent about source-code is things like this that need access to a ton of my data at all times. An app that only has access to the data I choose to share with it, I'm more willing to give-and-take on the show-me-the-code front.

As far as subscriptions go, a lot of devs have moved to a subscription-train model, which I really like: you pay for the subscription (which funds development and pays for support), but at any time you can _stop_ paying the subscription cost and keep the version you're currently running without further updates. That's a good trade-off to me, since I can choose to end my subscription without it becoming a catastrophic migration event that has to be carefully planned and executed fully before opting to stop paying.

No source - no pay. Even if source, in case the licensing scheme is subscription-based, there better be some service rendered that has recurring expenses, otherwise -- still no pay.

yes source - still no pay. What is the benefit in satisfying your demands? Code it yourself and make it open source.