You can dismiss their objections as childish, but people are gonna write in the language they want to (or are paid to) write in. If there's a large body of existing python code they'd have to rewrite in JavaScript, or use some python in the browser route for their purposes, why should we force other people to use typescript because some of us think it's better?

of course, LLMs, with their nascent ability to translate code into different languages, makes the question of rewriting something in a different language more tractable, but it's still a hike.