This information applies to versions: 2, 3
With macOS (v12.3) a regression was introduced, which considerably slows down the Apple Neural Engine cores used in all M1/M2/M3 Macs. This exclusively affects Fujifilm X-Trans RAW files in DxO PureRAW.
UPDATE: since the official release of macOS Ventura, this bug has been fixed by Apple.
If you are still using macOS Monterey (from version 12.3 and up), there is a workaround to let you continue using DeepPRIME with great speed: go to the DxO PureRAW’s preferences and under “DeepPRIME acceleration”, manually choose the option “Apple M1" (or M2/M3)" instead of the “Auto selection".