Hi Yves, I'm running into a very similar issue as the original submitter, however, when I'm running into it, I am *not* using the nVidia binary driver, but I am using a custom 5.15.44 kernel for a Raspberry Pi. What I found after digging for quite a while, was that, yes, downgrading to 1.26 would start Xorg, and upgrading to 1.32 would cause it to not start Xorg. After diffing the contents between 1.26 and 1.32, it seems that the option "logind-check-graphical" has changed from the default of false, to a default of true.
Simply adding in logind-check-graphical=false under the [LightDM] heading in /etc/lightdm/lightdm.conf shows it as starting again. This happened for me on both Pi3 and Pi4, armhf and arm64. I'm not entirely sure why this is the case, and the kernel hasn't changed on these devices since 2022-07-03 when we last built the kernel for them. Perhaps the original submitter could also see if changing that option works for them with the nVidia binary driver?