[qayxc]

It's all about observation bias. The SO survey wasn't representative in any conceivable way. Only active users (as already pointed out, the vast majority are passive users) who are passionate about their programming language of choice were sampled.

Most professional programmers aren't passionate about the language they use - it's a tool or a management decision, nothing to get emotional about.

The more "esoteric" or "exotic" the programming language, the more passionate its user base. Mainstream is defined by mediocracy and the average developer simply doesn't care.