Render and Replace audio doesn't actually render the "Essential Sound" fx

Well, I am really hating on PP this week, as I find bug after bottleneck after limitation... but this is one I can clearly ask about.

I'm using Multi-camera sequences all over my project, and the thing jams and lags constantly in my edit sequence.  I have narrowed it down to the audio render being an issue, because it finally works sort of smoothly if I turn off all the Essential Audio auto sound repair that I did in my multi-camera source sequence.  

However it's a terrible work-killer because:

1 - in the multi-camera sequence, everything plays just fine, with audio repaired by Essential Sound - reduce reverb, clarity, etc.

2 - when I put that MC sequence into a new sequence to edit, PP chokes, freezes, hiccups and lags.  Totally unusable editing.

3 - ok - so I will render the audio in my sequence and that will help - until I do any edit at all, and then the rendered audio seems to be discardedand we're back to lag and freezes.

4 - Hmmm - maybe I will render audio in the MC source sequence, so that it's a nice flavour that Premiere likes.  THen it wil play better.  No, when I hit "render audio" in the MC source sequence, nothing happens.  PP doesn't NEED to render it, it plays fine.

5 - Wow.  (hours between each of these steps by the way, as I struggle to figure it out).

6 - So here's a new thing - I can "render and replace" the audio in the MC source sequence, so the audio fx are baked in, that will make it play smoother right?  No.  When I "render and replace" there is no difference.  The new "extracted" version of each audio clip, still has "essential audio" effects added IN THE TIMELINE.  In other words, "render and replace" just made a copy of the clip and then added all the same effects that PP renders in realtime.

7- if I turn off Essential Sound, then I will have to re-do them because it doesn't save the analysis files.  And also remember each time I do a draft, to re-enhance the clips before export, and probably listen to the whole (laggy, unplayable) timeline through before the export, wasting a LOT of time and energy.

I'm at the end of my rope.  I tried opening up my MBP M1 16" 64GB to clean out the fans - no luck.  The GPU/CPU temps only had vage correlation to the problem anyway.  Also put a desktop fan and tried Mac Fans Control to get the thing cooler.  And I often quit, delete all cache files, and restart.  No improvement.

This is crazy.  Do people actually use Premiere Pro for multicam editing?  The number of crazy roadblocks to get to this current roadblock has been bananas - ie. sync 50 clips?  That'll be 150 video + audio tracks, sir!  Have fun dragging things up and down for the next hour...