Do all modern Fem seeds "herm"?

I've been growing on and off since about 2010, I've always used feminized seeds. Only time I've ran regs was some TGA gear back in the day, jacks cleaner I think. Anyways, my most recent stint growing is from about July 2020 to now. ALL the seeds (fems) that I've ran since 7/2020 have "hermed" on me to some degree, it almost always goes like this. Germ, Veg for ~5 weeks, flip 12/12, 2-3 weeks later right about when the stretch is done I'll start finding balls up and down the bottom half of the stems, some worse than others. I've had maybe 4-5 that didn't do it and stayed fully fem. I've tried everything environmentally to try to "correct" it, I was growing in a tent in my bedroom, so sometimes the light in my room was on when the tent was off. Tried putting the tent in the basement where it stays dark, tried basically sealing the tent to where the only openings were my intake duct and exhaust duct, even tried covering all the ducting in case it was letting light in (not the openings but the duct itself). Tried turning my lights down, raising them up, my temps and humidity don't fluctuate but maybe 2-4F and ~5%rh. I'm stumped. I've seen people comment that its common to find a nanner late in flower or maybe a ball or two on a stem if you get a light leak or something but idk, I know its been a while but when I was growing last in like 2013 or so I don't remember getting any male flowers on my plants, admittedly I didn't have the knowledge I have now but I still knew what a male looked like lol.

So basically TLDR;

Do all fem seeds "herm" or pop balls regardless of environment?

No. I've only had one hermie ever, and that plant was stressed hard.

I've mostly run fems, but also a lot of regs. I'm pretty sure the hermie was a reg. I forget what the strain was though.

I've had hermies on both fem and regular seeds.

I've had no hermies on both as well.

Shit genetics is generally the culprit for a true herm.

Stress and funky genetics is generally the cause for nanners

No.

Never had a herm with fem seeds.

No.. Not all fems..
Depends on the cultivar mostly..
For example, true arcata cut trainwreck fems will throw out nanners the last week or two..

What's the airflow like on the bottom of your plants? if the balls are mostly showing on the scraggly undergrowth not getting the light try cutting that stuff out before/during the stretch?

No

You have to remember that many of these "Modern" strains are just pollen chucks from people with no actual experience in breeding and are pumped out as fast as they can make them.