For example, I know what I am doing should work with Perl as old as Perl 5.8.8, and I do a <use 5.008008;> to verify this.
Eh, no. That use statement doesn't verify anything in that regard. It does prevent someone with 5.8.7 to run your code though.
However, should I make sure my code works with earlier versions of Perl?
That depends. Who are you programming for? Who are your customers? Do you have to make a sacrifice to support 5.6? If so, what do you get out of it?
many CPAN modules are fairly old, and their coding style is dated.
You know, if I'm considering downloading something from CPAN (or from anywhere else, whether it's free or paid), I seldomly give a flying fuck whether the coding style is outdated or not. The only
If you buy some meat, do you care whether the butcher uses modern knives, and do you avoid a butcher who has used the same knife for 20 years? Would you refuse to have your packages delivered by FedEx if they'd use a plane which was designed in the 20th century, opting for the bicycle courier who has written "use strict" on his 2009 bicycle frame? Do you only listen to music produced in the past couple of months?