The biggest cost of RSS feed items as a consumer is figuring out whether something is worth reading. A lot of feeds these days don't provide anything useful in the body to make a determination on this, and others just dump the entire contents in the body, which means you're wasting a bunch of time reading N% of something until you realize you're not interested in it and it can be skipped.
In addition to this, RSS feeds tend to be structured to just throw everything at you, regardless of the topics you are interested in.
For a few years I have been publishing my own topic-specific feeds[1] for others to consume where I fill the body with my own personal highlights from the source, with a link through to the source (ie. the things I found interesting, the "hooks" that give a quick signal to a consumer if this might be something they want to invest time in reading). They have a couple of die-hard consumers, but ultimately this really a case of a niche within a niche.
I wish there were more feeds like this for me as a consumer, but unfortunately I get the feeling that this idea will never really become popular enough to catch on widely as RSS becomes less and less relevant to the mainstream.
[1]: my software development topic RSS feed for example: https://notado.app/feeds/jado/software-development