David Banks I don’t know which OS you’re referring to but XP comes to mind. Since Microsoft doesn’t feel like updating IE even with its own Edge browser.
The truth is: XP had a product lifecycle that is over so it doesn’t make financial sense for corporations to invest on supporting it. Besides in the capitalist economy where buying means profit, they don’t see any reason to support users with small pockets :) Fortunately there is an alternative. I myself have a cheap machine at home that runs Lubuntu (the light version of the most popular Linux distro) and Firefox (which has hugely improved its performance and memory consumption since version 57). One can even have a cheap setup with Raspberry Pi or Asus Tinker or any second hand laptop that’s not more than 10 years old. Though the current fixes for these security issues makes the OS even slower (claimed not to be noticeable).
But the new OS might run the browser smoothly while it cannot run the other programs you are used to so it’ll all become one huge learning curve that consumes your time.