Probably because JetBrains only recently added native LSP to IntelliJ[0] etc.

Given that writing anything in Java/Kotlin basically requires the use of IntelliJ, it’s not really surprising that a language built on top of Truffle and GraalVM, all Java technologies, would ship with an IntelliJ plugin, _but not_ an LSP. Because such an LSP would have been useless in the primary IDE used by the language developers.

So if you wanna blame anyone, blame JetBrains for deliberately making hard to use LSPs with their IDE. Presumably to build a moat around their plugin ecosystem.

[0] https://blog.jetbrains.com/platform/2023/07/lsp-for-plugin-d...