Jagged/Blurry Fonts on Asus Display (PA278QV)

Like many other folks these days, I bought a monitor to connect to my 2018 MacBook Air: 27" Asus ProArt display. Videos and images look gorgeous. Fonts: pretty bad, especially on Apple Mail, but really everywhere. I've got everything connected via a Nucleum USB-C 7-port hub using the HDMI cable that came with the monitor.

Things I've done:

-Checked "Use font smoothing when available"

-Scaled the display resolution from the default (2560x1440) to 2048x1152, which SEEMED to somewhat improve things, but not enough.

-Followed the instruction on this site to "Adjust the Mac Font Smoothing Settings via Defaults". This is way above my pay grade, but I did it and the computer didn't blow up. Still didn't fix it, though.

Thoughts on a solution? Hardware? Software? Is the monitor too big? It's bad enough that I'll return the monitor if I can't fix this. Already staring at screens longer than usual...

Thanks for answering my first-ever Apple Community question :-)