I thought the Riley Ellie kiss was fine. Melded well with the story and was sweet. I thought the trailer was shot to maximize social agenda impact.
Edit: and for that matter - it worked, as I saw multiple sites reporting on "That" kiss.
Maybe it's just me but I do not think about these agendas in the slightest when I game. It's not even in my radar so I didn't see it as pushing some agenda. Besides, even if they are, what are they pushing? the normalization of gay relationships? it's already accepted or at least tolerated, aside from the religious groups pushing their OWN agenda on something it doesn't even affect them on a personal level.
I will give you that the kiss didn't mean much and it had more of a WOW factor than anything else. I hope it is more meaningful during the context of the story and their relationship.