Compatibility with Dell u2913wm monitor

How can I make my Dell u2913wm monitor work ok with my MacBook M2 Pro?

1. If I connect it to the HDMI output the colors look very bad and pixelated. I can't use it for more than 10 minutest because my eyes hurt...
2. If I connect it using a dongle/adapter it's a little better, but they're still wrong and everything is still pixelated.

I bought many adapters until I found one that finally works. I used to be ok. I moved and I had to use it without the monitor for a while. MacOS had some updates since then and now everything is just not right.

I tried changing color profiles, reseting the monitor to factory settings and all other fixes from the first 4 pages of Google results. No improvements.

I work with designs and I really depend on having a good quality image (that's why I own such a monitor) and I would really like to not have to replace an expensive device that works fine. I'm sure it's just a compatibility issue.