A lot of people have strong emotional connections to their artistic tools like instruments. It's a very common reaction to feel discomfort at the sight of an instrument being destroyed. Emotional attachments are irrational, but the point of an advertisement isn't to be rational otherwise they'd just show a spec sheet as a still in a video.

You didn't see the trumpet that was the focal point of the first few moments? The piano with paint cans prominently shattering right after that? The guitar towards the end?

Honestly no. First time I saw it, I just thought “huh they’re crushing somebody’s office”. Didn’t pay any attention to what was inside.

Wait....how did you watch the ad and not look at the images in any detail? There were multiple close ups of instruments.

Dunno... I guess I just saw the first shot, thought "huh, they're crushing a room" and zoned out. It all just registered as "stuff in a room" not "expensive musical instruments".