I've noticed
That overloading anything - washer, spinner, dryer leads to massive wrinkles.
As does over-drying.
My AEG tumble-dryer in Germany back in the 1980's had an incredibly complicated sensor logic - all aimed at getting the clothes dry without going too far. Reverse tumbling, cool-downs, etc. It worked really, really well at preventing wrinkles. Laundress could answer this, I don't know - but my feeling is that washing heavy and light items together, small and large results in fewer wrinkles than washing all light items together in one load.
Of course, given our allergy to synthetics, we keep mangles and steam irons close to hand in our laundry room. To be honest, though, I'm not all that hysterical about wrinkles. My better half spends 30 minutes ironing clothes every morning, including the boxers.