Unanticipated race condition perhaps? A process takes 2 minutes instead of 5 seconds, and then a later part of the startup fails because it has no way to handle the totally unexpected lack of data

For starters Chrome will not wait for extensions to load/initialize. Its possible in case of HDD there might be more things that simply time out/chrome disables because it doesnt want to wait.

JIT. It's using a "known state"/ cached blob to start then quickly falls apart as it does it's "SSD expected" memory management voodoo.