Spend time in any Reddit Bike Fitter thread and you'll see that not even two professional fitters can agree. So I chuckle when folks speak in absolute terms about another rider's fit. Perhaps they are plenty comfortable and are still achieving the results they're looking for.

I had a fitter who did just that, pretty much turned his back to me to look at his computer and only turned around to make changes to the bike that fit in the angles the computer wanted. I was on a bike where native stack/reach was already 560/390, he added an additional 45mm of spacers and put me on an 80mm stem, and saddle almost fully pushed back on the rails. I said its painful but didn't seem to matter.

I'm 5'9" or 175cm with an inseam of 32" or 81cm. I went to a new fitter and she did't look at numbers or angles a single time until I was in a comfort zone, now I'm on a QuickPro AR:One size small with a slammed 110mm -17 stem, and 25mm offset seatpost. So over 8cm difference in stack height between fits.

I struggle with the modern progressive fit because a higher stack loads my hands and wrists. With anterior pelvic tilt and a good amount of flexibility i need saddle to bar drop to be high to get hamstring and core engagement and unweight my wrists.  It seems the more forward I move the saddle the lower I need the handlebars to be.