Yes, it is infuriating, but getting mad at the situation only makes things worse. It isn’t like they will change or “get better” - you (hopefully) get better from a cold or illness. You don’t exactly “get better” from old age.

If they listen to you at all, consider that a win. If they are financially in decent condition, that’s also a massive win. If you can convince them to improve their health that has the potential to help the situation - eat better, maybe go for walks around the neighborhood.

I am going to assume that you don’t live with them, so one thing that has helped my mother tremendously is getting her an iPad. Both parents (who are older than OP’s parents by quite a bit) are not tech savvy in the slightest bit (I can not stress enough how NOT techie they are), plus their native language is not English, so communication for them has always been a little difficult. But getting my mother an iPad and installing Facebook on it was easily the best gift ever. She is able to communicate with relatives she hasn’t seen in decades. She can video chat with people 1/2 way around the world. It really is pretty amazing, especially since before the iPad, she’s never used a computer or had an email address or anything like that. Facebook gets a lot of well-deserved hate, but set it up for them, block whatever you can block and just make the it as streamlined as possible for them to use it. The large screen size on the iPad works infinitely better than a small phone screen.