So it’s fixed. What’s windows’ excuse? :-)
\\.\Volume{3558506b-6ae4-11eb-8698-806e6f6e6963}\Windows NT and UNIX are much more similar than many people realize; Windows NT just has a giant pile of Dos/Win9x compatibility baked on top hiding how great the core kernel design actually is.
I think this article demonstrates that very well.
Two other people were able to concisely explain the problem instead of being rude and condescending.
Fixed that for you. It used to be normal to use the device path (/dev/hd* or /dev/sd*) to reference the filesystem partitions. Using the UUID or the by-id symlink instead is a novelty, introduced precisely to fix these device enumeration order issues.
Only if the machine's BIOS is configured to give bootable USB devices boot-order priority. So it's not about Linux -- in fact, the same thing would happen on a Windows machine.
Remember that in a properly configured Linux install, the boot partition is identified by UUID, not hardware identifier (in /etc/fstab). Consequently if you change a drive's hardware connection point, the system still boots.
I think the concept of drive letters is flawed.
Otherwise, the drive letter is allocated statically and won't be used by another volume.