I've lived all over as well. The Denver metro is about as friendly as Austin metro in my opinion. Texas as a whole is friendly because it's the south, but that pertains to non urban areas.

I do find people in the West to be poorly mannered but not unfriendly. Frankly, growing up in the South, people in other places have bad manners in general to me.

I think it's important to know that companies have different cultures, and your experience of Austin or Denver can be heavily affected by that.