1. Discoverability 2. Monetization
Consider YouTube - it provides discoverability through the algorithmic feed. Giving creators a distribution platform they can't find anywhere else. It also provides monetization through ads, sponsorships and direct support to creators.
Consider Newsletters - no discoverability built in, but it does support monetization. Pay to subscribe, and only you will get the newsletter. RSS feed can't limit only to subscribers.
I've been a heavy RSS user since 2005. It has served my purposes well and I'd just as soon it not be "disrupted", personally.
Authenticated rss feeds are a thing. I have subscribed to some premium podcasts which have a auth token in the feed url for authentication.
This allows paid content, and most importantly revocation of access at a later date (if e.g. the subscription is cancelled).
This practice was common when RSS was popular and is still used today by newspapers and other media outlets.
An individual feed provides only a snippet view of the article which encourages you to visit the site where a subscription was required.
Patreon has this feature with their podcast RSS feeds.[1] When you subscribe, you get a URL with a personal, unique parameter. This feed has all the episodes that you pay for. Your version of the feed stops updating after you cancel your subscription.
[1] They probably also have it for normal RSS feeds, but I've only used their podcast RSS feeds
Why would I want to build an audience on a platform with no monetization possibility, ever?
Even sponsorships are not possible, since I can't reliably count reads (which I can even in email).
It's nice to think of the "classic" internet, but it's a naivety that will keep RSS on the edges. And I love RSS idea! I want it back! I hate subscribing to email newsletters in a way that makes it hard to manage and organize.
But, yes, RSS was always pretty fringe. And today there's enough hope being dangled that a newsletter or YouTube channel will make it big that it's even more fringe.
I do it to hopefully help people out in life. I get enough traffic and thank you notes to make it worthwhile.
The feed doesn't give you the whole article. Only the first paragraph or two. If you've ever seen someone write "after the jump" they're referring to the content that you can only see when accessing the page directly.