Exports run as normal with Max Render Quality selected, but it has no decernable affect on quality of output. Primary use case is exporting UHD sequences at HD. The sequences contain some assets that are upscaled in motion settings on the timeline and then subsequently downscaled as part of the export. Previously using Max Render Quality has functioned similar to AE's continous rasterization and subsequently exports of upscaled-then-downscaled source material show no quality loss compared with the original source file. However, in the current version there is a noticable quality drop as if Max Render Quality has not been checked.
Premiere Pro Version 23.5.0 (Build 56)
Media Encoder Version 23.5.0 (Build 51)
MacOS Monterey Version 12.4
Mac Pro (2019) Processor 3.2 GHz 16-Core Intel Xeon W Memory 192 GB 2933 MHz DDR4 Startup Disk Macintosh HD Graphics AMD Radeon Pro Vega Il 32 GB