My battery health has gotten awful recently too. I’ve got a series 5, so yes it’s 4 years old, but I genuinely only get about 12 hours of battery life these days. I went through and uninstalled every single app I don’t use, but it’s still awful.

Love everything else about it though, so I set a slickdeals alert to hopefully pick up a cheaper series 8 sometime between now and when the series 9 launches