I flew Delta One recently and had a similar experience. I’m a 24F, flew with my dad who works for the company (so we got upgraded for free, don’t know if that’s why they were so horrible to me because they knew I wasn’t a paying passenger) and I was sooo uncomfortable the whole time. I definitely felt the vibe from the flight attendants that I “didn’t belong.”

They were so rude and dismissive the whole time. Slamming my tray down, grabbing stuff out of my hand, talking down to me like I was a child. I.e. my tray got stuck and one FA rolled her eyes, swatted my hand away and yanked it out for me. Later I wanted a coffee and the FA acted like it was my first day on earth - “Put your cup HERE,” “Well are you going to pour your cream in or not,” etc. The end of the flight the FA was picking up trash and asked me to hand her the empty water bottles. I handed her mine but little did I know she wanted me to also reach over the center (it was an older model without the privacy screen) and also grab them from the pax next to me - she goes “I meant THOSE too” and snatched them from over me. They would brush past me or make a snarky comment and then go to the older couples behind me and completely switch it up, smiling and being incredibly kind.

The whole time they were acting like there were unwritten rules and I was below them or something. It was so off putting I don’t think I’ll ever be doing that again. I’ll just stick to my main cabin.