Anyone using older macOS versions here? How is your PC holding up?

I'm on Mojave 14.5 and I'm considering going back to Sierra or even El Capitan.

I started using macOS on Mavericks (the best version of all) and now I feel like there's not much improvement in the OS for it to be updated every year. The dark mode is amazing but other than that Mojave it's giving me a hard time. Most new apps (paid or free) aren't optimized for the last version (according to macOS itself), and the font is also kind weird here. I applied the fix for macOS Mojave blurry fonts but it's still not as good as it was before (24 1080 monitor).

I wonder if anyone is using an older version of macOS and is happy with it. My main concern is with apps not being supported. I know Apple software always requires the last versions of macOS, but I wonder how other developers go about it.

Thanks.