I use it literally everywhere out of habit, I got made fun of for using it when pulling out of my moms driveway once lol
The only reason I won't possibly use it is when I'm in a turn only lane at a red light and don't want to listen to it for 3 minutes
Most people I find only use it 75% of the time at best.
I'm 2.5 years into driving and am curious if it's just what semi-new drivers do or if I'm the odd one out.
Yes. I always use them. I hate when people don't. Oh, so you needed to come over? I would have slowed down if you told me. What are you slowing down for? Move- Oh. You're turning. Wish I would have known that. Dang, I need to pull out and make this turn. Let me wait until that car passes... Oh, they're turning.
It's such a small thing that makes driving safer for you and the people around you.
Currently I'm staying in Thailand the road culture here is fascinating. There are very few actual rules that people follow but its all about speed and projecting what are you doing so signals and everything is a big part of road culture here despite many drivers don't really knowing road theory.
For example if you drive up a curvy mountain road you horn on the turn slowly to project that you're driving there.