I never have trimmed these back. They've been in for 3-4 years now.

Same with me; I have not trimmed any. Sort of. The last time I had to do pruning on a hydrangea was when I did some roof work and the contractor said I needed to dig two of them out so they could access the roof thru that spot. Had to extract them, put them in a temporary place and replant them back. That was as close as I got to trimming.

They look like Annabelle to me. Mine bloom on old stems and new. Mine are in a spot that gets snow dumped from the roof in deep snow years, so some years I have to prune them severely due to damage, and some years they get pruning only to remove old blooms. In the years I prune severely, I usually get larger bloom heads, but not as many.

It could be something a bit less common variety like Ryan Gainey. Annabelle is the most common H arborescens though.

Looks like annabelle to me.

My hydrangea are in a bit of a protected spot so far as snow. They're on a northwest-ish facing wall with a narrow probably 3 mower passes wide width of yard and a single car width of driveway between our house and the neighbors' house. I wasn't sure how they'd do since the sun goes at a diagonal in that bed whenever I have looked and I've had issues finding something that would grow there. The foxglove and columbine I was told wouldn't survive love it too though. The foxglove loves it a bit too much.

When the hydrangeas really get blooming their flowers are bigger than my toddler son's head. They stayed green a lot last year which they hadn't done before...generally just white.