I have found that if i change the scale to 100% in the windows settings, i can get the UI scaling to come up with three options. The largest options is still way to small for my eyes, the create new button is still only 25mm wide and most text is 4mm high. I want to be able to use illustrator without needing a blemmin magnifying glass. Indesign seems to fit to the screen percantage when i enlarge it.
This is not ideal as i want all the rest of my programmes to be large too.
Reverting back to being 140% scaling and working in tiny illustrator. This is really something that should be fixed.