i don't have and i never had this problem with b.briefs. Like you, i commute everyday by bike and i know that my outer garments wear out faster due to friction with the saddle.
Are you wearing jeans? Maybe the problem is not the briefs but the trousers? It may even be from your posture 🤷
No I don't wear jeans. But that's an interesting data point! Thanks :)
What material have you been wearing?
Cotton
That's a large part of your problem. Go for sport's-oriented synthetic fabrics.
That's a good idea, thanks!
For years I've commuted wearing these:
https://www.planetx.co.uk/products/on-one-performance-fit-under-shorts-with-pad
Like boxers, but slightly padded, comfortable to wear.
Do you keep em on all day?
Normally I'd exchange them for normal underwear when at work, but on a few occasions I wore them the whole day, and it was okay (depending on the sweat level of course).
For a few years now I've been wearing bike bib shorts though, since my commute is longer now.
A place on the fediverse to share and discuss about commuting by bicycle