They're not just "important", a blog without RSS/Atom feed is like a car without wheels.

I’ve never had an rss on any blog/site I’ve ever hosted and never felt like I’m missing anything

What is the advantage to me of maintaining an rss?

Is there some giant rss feed following community I’m missing?

Chrome mobile used to have a native RSS Following feature since 2021.

https://blog.chromium.org/2021/05/an-experiment-in-helping-u...

It seems they killed it in 2025, maybe to make space for the AI button.

Is there some giant rss feed following community I’m missing?

Yes

Do you think I'll just check manually every day to see if you wrote a new post? That for each and every blog I follow?

That's like comparing old school Windows software updating where you "just have to go on the website and read the news" vs `apt update && apt upgrade`.

My assumption was that nobody checks rss feeds since the iPhone came out anymore, but apparently I’m wrong

Currently, the RSS feed is what's driving the most traffic to my blog.

You don't have to maintain it, you make it once then it just works. As long as your website can print post titles and urls to a document the rss feed should work.