As previously announced in one of VRChat developer updates, VRChat will be introducing new maximum limits for uploaded avatars.
PC avatars
  • Maximum file size: 500 MBs -> 200 MBs
  • Maximum estimated memory usage: 1200 MBs -> 500 Mbs
Quest avatars
  • Maximum file size 10 MBs (unchanged)
  • Maximum estimated memory usage: 40 MBs (new)
The SDK will warn you if your avatar exceeds one of these limits. We came to these numbers based on an analysis of currently uploaded avatars. If we find legitimate use cases that we missed, we might change them. About 2% of avatars will be affected.