This is making the rounds. If you’re using external monitors that aren’t “retina” (less than 4K including some of those ultrawide QHD monitors), this BetterDummy app might be useful.
Unlock your displays on your Mac! Flexible HiDPI scaling, XDR/HDR extra brightness, virtual screens, DDC control, extra dimming, PIP/streaming, EDID override and lots more! - waydabber/BetterDisplay
I actually installed this, Dave, but had some problems getting the right aspect ratio out of it. The instructions are a little tricky where you have to set up a "mirror" display in preferences.
Really, I am getting a really nice resolution on my 4k widescreen monitor and I am not sure this app could have improved upon it.