I would go nude if I could but.... Any thoughts about going commando to work will anyone be offended? The material is very thin but length is adequate.
I don't even own underwear, and I do wear shorts to work. The key is, get so used to it that it doesn't matter anymore.
Also, men's shorts have gotten so long now, it really doesn't matter. If you wore your 1970's shorts without underwear, then your genitals would likely be seen by coworkers.