I’ve literally seen them chase me and avoid others I am with. I also do react and get welts/itchy, but they 100% are also chasing me more than others.

I think how much they're attracted to you and how much you react to bites are independent. My daughter and I can be in the same place outside for a while and she'll end up with many welts while I have nothing. I do catch them biting me sometimes but she just gets swarmed.

I'm pretty sure as a kid I got a lot more bites. My kid's a teen so I wonder if hormones play a part.

The latter for me absolutely.

Mosquitoes have never left any kind of mark or bump or bite on my skin.

I can sometimes feel them biting (injecting? whatever) and I smack/brush them away but that's the most nuisance they cause.

I've always wondered why.

Possibly both. I've certainly observed mosquitos biting people who say they don't get bitten -- they just don't notice, which may not be a good thing.

I’ve tested my dreaded mosquito tastiness. I always count bites after a hike and compare to others. No one ever comes close.