A big difference between the Perl/PERL prejudice and the ones you've posted (aside from the fact that yours cannot rationally be defended as being accurate IMO) is that it concerns something someone does as opposed to something someone is. Using the wrong case when spelling perl is a mistake, same as a syntax error when programming. If I were employing programmers or looking at a prospective boss, I would prefer candidates who do not habitually make syntax errors, and that is a perfectly valid prejudice to have.
Debugging is twice as hard as writing the code in the first place. Therefore, if you write the code as cleverly as possible, you are, by definition, not smart enough to debug it. -- Brian W. Kernighan