Some of the best architects have been the most difficult to type.
That won't stop people from developing their own stereotyping.
The same thing happens in all artistic fields, from music to painting to whatever. People who are (obsessive) fans see minor subtleties as important differences, people who are simply looking for a cursory overview will only see the basic similarities. How many times have you heard someone say that all the music of someone you like all sounds the same? You naturally think they're crazy.
Heck, there's posters on here - who are almost by definition obsessive fans - who prefer to see things only in broad generalities.
Rich G and redanman had a French saying for it, something about chickens and gooses.