Google killed it in 2013 as part of one of their "spring cleaning" purges, said usage was declining. people are STILL mad about this one, it's become the go-to example of "don't build your workflow around a free google product." a wave of RSS readers popped up afterward to catch the refugees.
RSS as a format never fully recovered from this in terms of mainstream usage, even though a lot of us diehards still use it daily.
the shutdown backlash was so intense there was literally a petition with over 150,000 signatures asking Google to keep it alive. didn't work obviously.