Not me (I’m a July birthday and love it!) but DD and DP are December and DM is January.
So far DD’s early December birthday has been surprisingly fine - people are in a festive mood and not yet partied out, and it’s far enough away from Christmas that the two celebrations don’t merge together. They’re in the midst of doing fun Christmas-themed stuff at school, and she’s unlikely to ever have a major exam on her birthday (unlike my early June born best friend, who hated this aspect of her birthday!) DP and DM’s are harder - DP’s mid December birthday does tend to get a bit overlooked, and DM’s is the worst (post-Christmas blues, having to think of yet another present, no one especially up for celebrating).
With DD we’ve found you have to be a bit creative when it comes to parties, due to the weather and the fact that so much is geared towards Christmas (eg our local family theatre does special birthday party/show packages, which DD would have loved… but not in December). It is a bit annoying having birthday and Christmas celebrations/gifts within a few weeks of each other, but it’s doable. But we consider ourselves lucky, as DD’s original due date was Boxing Day, but she arrived early!
I definitely wouldn’t wait. As a primary teacher I saw how the older children in the year were largely more confident and found the early years of school easier, which to me is a much bigger issue than the timing of birthday celebrations. And while I now love my summer birthday, as a teen it was a pain being the youngest and last to reach every milestone.
So, as with everything, there are pros and cons, and I definitely wouldn’t avoid ttc to dodge a Christmas/January birthday.