It's not much overhead?
The problem is what happens next. Do you reload the entire page each time the user makes any kind of change?
I suppose what you have to learn and add is relative to what you already know and have, isn’t it?
What reason is there to learn Ruby and Rails and Hotwire and streams and turbo frames and whatever the next churn is just to avoid rendering some html with javascript?
No one is suggesting the industry immediately adopt some random new library, except for Rails fans who constantly demand everyone abandon a de facto standard like React and use their new toy.