It really depends on the LSP implementation. Some are pretty bad. Some are really good. For example, Jetbrains Webstorm uses the same Microsoft LSP server as VS

It really depends on the LSP implementation. Some are pretty bad. Some are really good. For example, Jetbrains Webstorm uses the same Microsoft LSP server as VSCode. Typescript support is really good in VSCode. I also find the golang LSP server to be pretty comparable, although it could use some polish. Another area where VSCode/LSP blows away Jetbrains is with C/C++ code, using something like ccls, and rust with rust-analyzer. Like I said, in my ideal world, Jetbrains would simply provide commercial LSP servers for all of the things they support. Like you said, they have some of the best in class IDE support for various languages, especially JVM.