Someone posted about what sounds like this same issue in January here. They found that, for whatever reason, unplugging the ethernet cable (thereby disconnecting from the internet) solved the issue. I tried simply disabling my ethernet device, and sure enough the project load time from cold start was normal (about a minute).
I spent most of yesterday trying to debug this to no avail. The workaround is great because of how easy it is to toggle the ethernet device, but understanding the root cause would be even better. I’ve of course asked AI, without much luck. I just went through the process of disabling all the suspicious plugins including TCP and UDP Messaging, and the various telemetry plugins (Editor and Runtime Telemetry) as well as the Studio Telemetry plugin (which doesn’t appear in the Plugins menu in 5.6) as mentioned in the threads linked below.
Nothing seems to work.
PC Specs:
CPU: 9900X
GPU: 9070XT
RAM: 64GB DDR5
Storage:
Project | SATA SSD
5.6 Engine | m.2 SSD