Is anyone else annoyed by the inaccurate use of the name "tri-tone"? I'm guessing a real tritone would be far too anxious as a phone sound for most western ears.
My co-worker's office phone is a real tritone (https://en.wikipedia.org/wiki/Tritone). Considering that her desk is right next to mine, I find it incredibly jarring to hear that interval blaring in my ear whenever she gets a call.
...but in the end, I think you're right. I've been trained by Western music to think of the tritone as anxious or dissonant.
Your anxiety at the tritone is not just a culturally learned response - as the Wikipedia article you linked explains, the harmonic ratios in a tritone really are mathematically 'dissonant' when compared to, say, a perfect fifth or major third.
A mathematical explanation of consonance and dissonance in music is appealing for its simplicity, but it is somewhat of a reductionist approach to understanding listeners' experience of music. There are many elements of the European musical tradition that, though they sound consonant to our ears, cannot be explained on mathematical grounds. The minor mode and the minor triad are notable examples. A more subtle and insidious case is that of equal temperament.
I don't know if the tritone in the ring grandparent comment mentions is a melodic (2 notes in sequence) or harmonic interval (2 notes at the same time). In any case here is how a tritone interval sounds:
...but in the end, I think you're right. I've been trained by Western music to think of the tritone as anxious or dissonant.