Yeah: it's just rude. I don't think it's personal about you, I think it just reflects poorly on your T.
But there does seem to be a generational shift, at least in US culture. I've always received a hand written card/thank you note from my Ts when I'v given a gift. But my Ts were always older than me, of generations that were brought up to do so. I was brought up the same way: from childhood, thank-you notes were written a couple of days after Christmas to demonstrate appreciation to those who cared to send a gift. It was part of the rhythm of the holidays. Judging from what I hear from a lot of people, it's much less common now. I think it's sad, and it would bother me.