MacOS 15.4, adjusting accessibility text size doesn't seem to do anything

I just upgraded to a 4K monitor. I'm trying to get the text size to be larger and the menu larger via the "Accessibility > Display" Text size setting. No matter what size I set it to, nothing changes even with a reboot. The text is still too small. I could set the display size down of course but I don't want to do that for all the pixels, just text. From what I've read, there's no equivalent in MacOS to the text rendering tweaking that Windows or even Linux allow, or at least not in the same way of working where the font rendering system itself could be controlled. I just fiigure that the Retina Display concept people would have a way to do what seems to me a pretty obvious display mode.