Yeah, I'm Norwegian, and maybe the Scandinavian languages makes us extra likely to make those mistakes, but overall English hyphen rules to a large extent boils down to feels. Words "graduate" to hyphens over time as and when they start to become seen as a unit, and then sometimes eventually fuse into words. E-mail to email is one of those. And that pipeline is also not uniform geographically so different English speakers will disagree about what should have hyphens where and when...