How many here anneal their 45 colt/454/460/480 etc... brass?

I've never annealed a straight-walled case. Nor have I ever noticed a need.

It is always interesting to question the status quo...however I think the headstamps of my handgun brass will become unreadable before I get more than a handful of cracked cases, even when slightly belling a case with a powder die on a Dillon 550.

Most cracks I have had in straight walled pistol cases have been in the middle of the case, not at the mouth.

I have fired some of my 38SPL brass so many times that the head stamps are peened off them. Way more than 100 reloads so far. The few splits I get on my straight walled handgun brass are almost always in the middle, not often at the mouth it seems. This for 357MAG, 44MAG, and 45 Colt as well that I reload. Never anneled any of them and feel the occasional split brass isn't worth changing my routine. YMMV

How many anneal???

Not me.
Infact I've never heard of annealing pistol brass.

I'm not saying its bad, but I just never heard of it.
Just my 2¢ YMMV

I won't even anneal bottleneck rifle brass unless it's so rare that I need to form it form another calibre.