I went up to an 18-20 from a 10-12 due to medication. I am now back down to a 12-14 and still dieting. I have noticed real changes in how I am treated.
I started one job when I was at my biggest and then another a few months ago when I had already lost quite a lot. Both central govt departments so not a million miles apart in terms of culture and the difference is marked.
At the last place, it was made very clear my face didn't fit and I was frankly treated like a lazy idiot, lots of snapping and mansplaining. I was overlooked and actually pushed aside in favour of people who did fit in physically. Here, I am treated with respect and given plenty of opportunities to develop, projects to work on etc.
Male attention has ramped back up but it is largely much more courteous. When bigger, I would be complimented and catcalled but it would often focus on my bust and bum and be very sexual in nature, rather than generally saying 'you look nice'.
I've been OLD for 2 years, always using recent pics and found that men would want to meet and go out but they'd be after sex and not much else when I was at my largest. Now, they seem to want to get to know me more seriously (obv currently I'm not meeting anyone in person).
I wouldn't have believed the difference if I hadn't lived it.