Hi @notworkingadobe,
Thanks for reporting this issue. We recently fixed a similar issue where certain settings were not being saved and that fix is currently available in our Beta builds. If possible, would you be able to install the latest After Effects (Beta) from the Beta apps section of the Creative Cloud app and let us know if the Memory & Performance settings are correctly being saved when AE is quit and relaunched?
We haven't heard any report of performance slowdowns in AE 23.2.1 on M1
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