Does anyone have good examples of this actually happening for end user software (like Ghostty is) and where in the long term proprietary fork won? Most of the recent variations of this that come to my mind are related to cloud infrastructure. Stuff where you have serious business customers.

And in some of those cases GPL wasn't enough to prevent it. Niche end user utilities, where original is available for free have little room for monetization. And in many cases existing users are already choosing the open source option despite the existence of commercial solutions, or where it's too niche for commercial solutions to exist.

Only thing that comes to my mind is VScode with all the AI craze. But that doesn't quite fit the pattern neither is the Microsoft underdog, nor it's clear that any of AI based editors derived from VScode will survive by themselves long term.

There are also occasional grifters trying to sell open source software with little long term impact.