There are two reasons:
- People don't know better (yes, they really don't)
- Language server allowed languages with abysmal tools to finally have some semblance of an IDE
None of us know the future, but in my opinion Fleet is a mistake:
- It tries to fight VSCode at VSCode's turf (an editor with primitive IDE functionality)
- while trying to be a testbed for new UI for JetBrains IDEs
- while trying to both serve the Language Server crowd and keep JetBrain's vastly superior language tools
- while diluting JetBrains' offer of development tools