And to take this further, outside of jr. high/high school, this ignoring is unintentional. I'm 5'7" which makes me tall among the shorts, but the number of times I've felt like I had to jump, to make sure other guys pay attention when I interject, is high.
I'm your same height and have never observed this. Frankly a lot of stuff I see online about supposed travails of being my height are bewildering to me.
I've generally found that in a professional setting, my height is not generally an issue.
However, if, at a bar, my height is considerably (>= 6-8") below the median of the people i'm hanging out with, interjection does require more effort than it does amongst those who are closer to my own height.
It may just be pure acoustics :P
[Edit: in case it isn't clear, this is in situations where everyone is standing]
Seated meetings/meetups are my friend.