Wanting to completely own one's tools is good on principle. However, with tools such as an IDE that remains largely theoretical because very few users will act

Wanting to completely own one's tools is good on principle. However, with tools such as an IDE that remains largely theoretical because very few users will actually change core IDE code. Therefore, for all practical intents and purposes it doesn't really make a difference if you own Eclipse or the IntelliJ IDEA Community Edition or a perpetual licence for the IntelliJ IDEA Ultimate Edition.