I use my turn signal all the time so I’m not one of these people, but here’s what I’ve heard from others over the years:

• there’s a video of one woman being asked on a college campus and she said it’s not “manly” for men to use their turn signals
• one cop on Reddit said he doesn’t use it when he “knows” no one is around
• my dad would get on my mom about it and she said it was a bad habit of not putting it on (whereas my dad stressed us to use ours when teaching us how to drive)
• I had a friend who brushed it off because “it’s just me being a girly girl” while making a stupid cute face gesture