I think the bald/shaved head look is something that some men can indeed pull off well but this is not the case for all men.
If a guy is relatively handsome, 6'3", has broad shoulders and is in shape I highly doubt him having a shaved head is going to make that much of a difference. A guy like this is going to look fairly intimidating and may not be for certain women, but other women may very well find such a man very attractive.
I think where you run into issues is when a guy is not particularly attractive to begin with, perhaps is short(ish), not very fit, possibly overweight, etc. A man like this may pursue the hair treatment stuff simply because he feels the need to hold onto every single point in regards to his physical looks as possible, as he doesn't have much going for him to begin with.
I started thinning when I was pretty young but started buzzing my hair at 24, went to the razor at 28, and I don't feel it made much of a difference. I'm also 6'4", lift/exercise regularly, and have a fit/athletic body (240lbs. with a 34" waist and 47" chest) so it's a bit different for me compared to most other men in the real world. The type of women that generally do not appear to be all that into me are those that are very young or those who seem to go for guys that are a little less manly looking, think those that date hipster types, etc. You aren't going to be every single woman's type, obviously, and it's simply just a process of owning who you are.