Because I‘m good in it. And my clients don‘t depend on me - they can choose to continue working with me not because I‘m the only one who knows how the language works, but because they WANT to.
Those who say that they just use htmx instead of frameworks, how does it work for you? Do you use libraries like alpine for client side interactivity or just write vanilla JS?
Using Alpine.js is not preventing you from also using vanilla JavaScript in the same project. Combined with alpine-ajax it‘s absolutely enough for progressively enhanced semi-dynamic web experiences. An example: https://filter-munich.com
I document technical things on my blog and hardly anyone reads it.
But later on when I need that thing again, I just go there and I have the perfect documentation available for the topic (it's perfect since I wrote it hahaha).
[0] https://musicforprogramming.net/latest/