If it powers 30-50% of the web, including thousands of major websites, it works at some level.

Ivory tower "just don't use a low-cost solution" people aren't going to hand over money to people to use a higher-cost one, are they?

And ignoring why it's used besides the sloppiness means they have a huge blind spot to what people actually want:

"wordpress is valuable because it allows very bad developers / marketing people to write very bad code and get away with it, driving extremely low cost solutions for clients who are cost concious"

Nothing in this quote doesn't describe very real needs.