Haha, well jean jackets are in fashion over here right now, I think I have 2 and my sister has 3. Guys do wear them too. But if your concerned tbh just wear whatever you like. Trends come and go but everyone has their own personal style.
For me it's not what the guy is wearing but the guy that's wearing it. Inevitably jean jackets will look sexy on a hot guy.
Jean jackets are really cool, as long as you don't wear it like a denim tuxedo. Make sure whatever pants you're wearing is at LEAST 2 shades darker or lighter than the jean jacket, or else you look like you need to find a time machine back to the 80's.
i think they could work for either gender. Its more of a staple piece that goes with a more detailed piece of clothing so if you can pull it off go for it and try it out! I love wearing my jean jacket all the time so I try to put it with everything!