RSS readers allow you to collect the articles of specific sources in one app, making it a lot easier to find the content you’re interested in without crawling through a lot of noise. RSS (which may stand for Really Simple Syndication, Rich Site Summary, or one of several other possibilities — nobody seems sure) has been around a while, having been first developed in 1999, although it wasn’t more widely adopted until a few years later.
Yeah. Anything worth developing takes up quite a bit of time and doing that for free doesn’t really work out for many devs. Only one I can think of that’s close to what you mentioned is maybe Thunderbird?