If I want to quickly pitch “you should follow X, Y, and Z using RSS because [problems with social media]” to people who have never heard of RSS, what readers should I recommend?

I want at least web (not self-hosted), Android, and iOS options. Native apps for Mac and Windows would be nice as well. Linux users probably already know what RSS is.

There absolutely must be a free option good for at least 25 feeds because unfamiliar tech is a hard enough sell without having to pay. I’ll grudgingly accept ads if that’s the tradeoff for something beginner-friendly.