There is a difference between good visibility and just annoying people. Many people who run with their highbeams on in the day don't care how annoying it is to other drivers, because all they care about is being "seen", when in reality, it can be more than just annoying- it can dazzle and blind some people.
High beams can and will blind and/or dazzle oncoming traffic in the daytime which is not only annoying, but also potentially dangerous. It makes it MUCH harder to tell where the bike is/how far it is away, or which lane it is in. This tends to throw away many possible safety gains.
If you want more front visibility, I think the best thing to do is to add properly adjusted, wide-angle driving/running lamps as far away from the headlights as possible. And preferably yellow for additional contrast. This provides more frontal area, a bigger apparent vehicle size, and more geometric clues for distance calculation. Plus it helps not only in the day, but also at night, and for more angles/situations.
