Mmm. I was trying to decide if they're mutually exclusive. I agree with @aradia22 in that talking about yourself, distinctively, without sounding as though you're bragging is a tightrope. It's a skill that even if people posses, they don't employ well. There are things I think work better than others: statements like "I love" rather than "I have", "name your favorite thing to do on a Saturday afternoon" rather than "I'm not into skydiving" but especially with online dating, you've got about 6 seconds to keep a reader reading, make it interesting, true and glimpse-y. By virtue of joining the platform and creating a profile, I think it is a sales pitch whether you acknowledge that or not. It's not as though it works differently in person. Flirting with a stranger is about throwing enough charm, funny and memorable their way during a temporary connection to hopefully create a second encounter. Don't get me wrong, sincerity pushes to the front of the pack, but if it were an attention grabber, "he/she had a nice personality" would be the start to every how'd you meet story ever.
Girl, it's killing me, was the next word gonna be childhood? lol. I also agree with you that it's not brag worthy, but disagree that it's bragging to begin with. For that guy, his backstory could be: I'm the son of immigrants and the first generation in my family to graduate from college - that could be his amazing accomplishment. Sorry, for the Chandler Bing delivery.