Laptop can't see external montior's maximum resolution

I've got a Lenovo IdeaPad 5i 15IIL05 with Intel UHD graphics, running Ubuntu 20.04.1. I want to connect it to an external monitor (Acer Gaming Nitro VG270U) via HDMI.

When connected, it does work - however, the highest possible resolution the system suggests is 1920x1080, when the screen itself supports 2560 x 1440. It is definitely not a problem with a cable or the monitor itself - when connected to another laptop (Lenovo Ideapad 3gen with AMD Renoir iGPU), running Ubuntu 21.04, everything worked well.

I also don't think it is a problem with the installation itself. Before Ubuntu, this laptop was running Arch-based distro (Endeavour OS), where the same problem occurred.

Usually then facing some issues like this I'd start by checking what xrandr tells me about the screens connected. However, the laptop is running Wayland, so it doesn't work - and, as far as I know, there is no tool to replace it. I don't really know what can cause this issue. Here is some system information:

corny@warri:~$ lspci|grep VGA
00:02.0 VGA compatible controller: Intel Corporation Device 8a56 (rev 07)

corny@warri:/sys/class/drm/card0-HDMI-A-1$ cat modes 
1920x1080
1920x1080
1920x1080
1920x1080i
1920x1080i
1920x1080
1920x1080i
1920x1080
1920x1080
1680x1050
1280x1024
1280x1024
1440x900
1280x960
1152x864
1280x720
1280x720
1280x720
1280x720
1280x720
1024x768
1024x768
1024x768
832x624
800x600
800x600
800x600
800x600
720x576
720x480
720x480
720x480
720x480
720x480
640x480
640x480
640x480
640x480
640x480
640x480
720x400

Where is also a suggestion of manually setting the resolution with video kernel boot parameter. However, I've tried several naming options (card0-HDMI-A-1, HDMI-A-1, HDMI-1), and it doesn't change anything - instead, it causes the internal screen to display some extremely glitched images.

I've also seen a suggestion to create custom edid and make the system use it. I haven't tried it (yet), however, I don't really see how that would help - if another laptop can "generate" valid EDID, this one should too.

What can I do in this situation? What can possibly cause such a problem?

Update: That is probably not a X11/Wayland issue - booting in X11 doesn't help, neither does adding custom resolution with xrandr --newmode.

Update: using custom EDID didn't help, either.