Ah, but 100 years ago, 80 years ago, even 50 years ago what we could afford had more to do with what we had than wanting the latest and the greatest. Henry Ford sold the Model T for $595.... it was Still WAY more than most people could afford so most people didn't have cars.

Conveiniance is a driving factor, as is innovation but cost and perceived cost have a heavy hand.

Think about how many men simply didn't shave or got a shave once or twice a year in the 1800's.... look at old photos.
I would wager that shaving was a luxurious endeviour for those well to do no matter what the era until recently and the skills for caring and maintaining a razor were not that much more commonplace in the 1800's any more than they are today.

I would also wager alot of our collective memory and interpritation of grooming habits from generations past are colored by today's standards. for example- We make movies of events that happened in the past. Real events, but we have no definitive exact record of what exactly happened, so we make it up based on what we think would have happened useing our knowledge and views. We assume there would have been daily dialog and happenings, so we create the scenes. We cast actors to pretend to be these historical figures and weave a great tale, yet we want themovie to be a success and forcing Mel Gibson, George Clooney, Brad Pitt, or countless others who make our ladies weak in the knees to be unshaven and unkept for the sake of accuracy in a role would likely lead to diminished returns because the "modern beauty" of these actors is...tarnished by their appearences.
Movies are a link to our collective memory.