After Effects 2025.0.1 performance drops on the home screen

as far as I know, that's normal. After Effects is 30 years old. it's really not made for modern computers, and has never been refactored in the last decade or two, so who knows what is happening in the backend. If you mean just an empty project, that would make some sense- as I believe the UI and backend, as well as RAM managment in the software is probably all working on one core. so you have simply rendering the UI, which is hurting performance.

of course, the home screen was never necessary, probs just to impress shareholders and jump on some overblown bandwagon or separate CC from the more useful versions in something other than worse performance, maybe because they thought VFX editors needed to have their hands held to do their job right. I still use CS6, which doesn't have one, and it starts up in a few seconds, and the UI is nice and snappy, and it needs less than 4GB of RAM to run smoothly.