> and forces you into a closed proprietary ecosystem

https://github.com/jetbrains/intellij-community ?

Exactly, I've been using their community edition for years for Kotlin development. Works fine for normal day to day development needs. I had a paid subscription for a while that I just let expire because I rely more on agentic coding tools these days and I just don't write a lot of code by hand at this point. The paid version adds a lot of deeper integrations and tools that you may or may not need. Personally, I don't really miss most of that. These days the community edition and the paid edition are the same. But if you don't take a subscription, the paid stuff is unavailable.

As a company, Jetbrains is a private company. It's one of the few large software companies that managed to get there without selling out to VCs or the vultures on the stock market. Of course they want to make a profit but they also create a lot of value for developers. Including a lot of open source things. I think it's nice that it's still possible to create a business by bootstrapping and without compromising your values.