The thing is the VS code handles everything (with extensions). If I want to use pandoc, or CSV to markdown table, python linting, Go, whatever, there’s extensions that can handle all of these equally well and consistently, for example format on save.
If I want to use jetbrains then the pycharm for python, intelliJ for Java, Goland for golang… Then there’s licencing depending on whether I’m using a personal licence or corporate laptop, whether I have to get a licence from my employer etc.
For me it’s not so much that it’s so good, but that it works with everything in a consistent and obvious way plus I can install it on any machine I might be using.