I spent the better part of the weekend trying to figure out why text was blurry on when using external displays on our new M5 Macbook Pros. Turns out unless you run macOS at a very low UI scale (making everyting look huge on a 4k display) it will refuse to render in high DPI mode - making text look dreadfully blurry.
Previously with earlier Apple Silicon Macs (my old M2 Max for example) if macOS refused to render cleanly at 4k you could use a tool like BetterDisplay or RDM to override the scaling and enable high DPI mode at 3840x2160 - that no longer appears to be an option on the latest M5 Macs and you're stuck at 3.3k~ (3360x1890).
*Note: Editorialised the title slightly to make it more descriptive of the limitation.
Previously with earlier Apple Silicon Macs (my old M2 Max for example) if macOS refused to render cleanly at 4k you could use a tool like BetterDisplay or RDM to override the scaling and enable high DPI mode at 3840x2160 - that no longer appears to be an option on the latest M5 Macs and you're stuck at 3.3k~ (3360x1890).
*Note: Editorialised the title slightly to make it more descriptive of the limitation.