Did you by chance get this figured out? I also cant boot kernel 6.14.x on my Fedora 41 machine
Interestingly enough, our machines are in many ways similar. Mine has a 28-core i9-7940x + 128 gb ram + 1080ti, so both are high core count / high memory machines with higher end nvidia GPU’s. Also, both of our machines have the root filesystem on a nvme drive. Not sure why, but I have a gut feeling that i important.
I was able to get into a dracut emergency shell and look around a bit. The problem seems to be that a handful of kernel modules arent getting loaded because they fail to decompress properly. running dmegs/journalctl also tells me that iscsi was requested but that the kernel/initrd doesnt support iscsi (even though the dracut iscsi module is included and the iscsi kmods are present in the initrd).
a bunch of block devices are also missing from/dev. My sata HDDs are showing up ok e.g., as /dev/sda1). But, my nvme drives arent appearing as block devices, and plugging in a usb flash drive doesnt do anything either. Notably, /dev/disk is missing entirely. Assuming we are htting the same underlying bug, this would explain why your boot freezes on accessing /dev/disk/by-uuid/...