Just as JetBrains is not representative of every dev, neither are LSPs. Some developers want a specialized IDE for their language(s), some want a highly customized editor with their language servers. As long as you efficiently produce code that works, who cares what other people use?
That’s because it makes sense when dynamically creating HTML. HTML is not a programming language, it’s simply markup - so if you want to generate some block of HTML in a loop and later access that block of HTML in JS (e.g. to interact with the UI separate from creating it in the first place), it’s a completely reasonable thing to do.