Sonoma, HiDPI issue, external monitor 21:9 - 34" - 3440x1440 165Hz

Hi everyone.

I have a MacBook Air 15 M2 connected to a Huawei MateView GT 34 monitor.

The native monitor resolution is 3440x1440 at 165hz, I connected the macbook with a USB type C cable (Thunderbolt 3/4) to DP 1.4 with 34GB band (UGREEN USB C to DisplayPort 1.4 cable 8K 60Hz 30Hz 4K 240Hz 144Hz HDR VRR Thunderbolt 4 3).

If I keep the default resolution of 3440x1440 everything is very small and in any case not very well defined (reading emails is complicated).

If I try to set the proposed HiDPI resolution of 1720x720 everything is extremely large and in any case not very in focus.

I would like something in between....

Now I can't understand why the system doesn't offer me further higher HiDPI resolutions.

I also tried using BetterDisplay but the result doesn't change.

Do you think the problem is caused by the cable?

I forgot the monitor has 109PPI - 21:9 format WQHD