I love that you have noticed what's happening! Yes, they're dropping like flies. BBC Countryfile - a regular - just scrapped the pages I used to pitch for and regularly supplied. Another one bit the dust last November and shut up shop. It's a disaster. I don't know if the work exists. I keep hoping to turn things around one way or another.
I did try Upwork but didn't get any work. The bidding process means anything worthwhile has a lot of competition, and you have to pay to apply for each job, and then the recruiters ignore you. It's like trying to apply for a position in a company - but having to go through the recruitment process for every single gig. They even want to conduct interviews if they like your application!
I've not given up on it, but I'm waiting to accrue some free credits before I try again. I refuse to pay to apply.