I resent the seemingly common belief that STEM and creativity are so disjoint.They're not, of course, and you explained that well. I do think that there is a problem of (surprising?) STEM anti-intellectualism, especially in industry. Some programmers are literate in history, the arts, and philosophy. Some are not. The latter category seems to get our industry in so much trouble; if they understood aesthetics, they wouldn't be so dismissive of languages that aren't Java, and if they understood human nature (through history and philosophy and literature) they'd have a better understanding of why "Agile" is dishonestly-sold bullshit. My 10x aesthetic sense isn't something I was born with; it comes from being exposed to a large number of seemingly unrelated topics.
At heart, I'm a liberal arts guy. I went to a small liberal arts college (Carleton) when I had several big-name schools in the bag (e.g. a contact at Princeton) because, when I was 17, I wanted to be a writer. I was more passionate about poetry than the sciences, at the time. I majored in math, though, and was able to transition into software. I definitely think that a broad-based, liberal education is important.
All of that said, a quality liberal-arts education includes math and the sciences. After all, two of the original seven liberal arts were mathematical, a third was astronomy and a fourth was music.
There are narrow scientists and programmers, of course, and that's part of why we encounter so much nonsense in our industry, but there are narrow history and English literature people (even at high levels) as well and they're just as bad. Scientific literacy is important, and the creativity comes from exposure to a large number of fields. Like you, I reject the idea that some fields (e.g. the humanities) are more creative than others (e.g. the sciences). However, I think that people who simply refuse to learn a subject, whether it's history or the sciences, generally aren't very creative.