There were two firmware releases yesterday: 20230809.f2eb058a-1 and 20230809.789aa815-1. The later includes kernel/git/firmware/linux-firmware.git - Repository of firmware blobs for use with the Linux kernel. However this commit might have added issues also to other AMDGPU hardware. I can try to do the similar way as Arch did and only update the microcodes of AMD and keep the other older firmwares. So check with an USB-Stick which of yesterdays firmware got installed on your end.
Also try a different kernel than 6.5 series … but your issue can also be something else. Check with a live-media if you can boot.