Take everything VCs / YC say with a pinch of salt. What was Facebook "solving" around the time Thiel invested? Nothing, it was a clone of so many similar platforms - more or less - with better UX. Just that they had traction to show. That was not a "zero to one" investment at all. Same with Whatsapp, same with Gmail,...
If you manage to show traction too, those rules go out of the window.
One rabbit or two rabbits doesn't matter. Question is, can you create a social platform where people feel like coming back again, and again, and again? That's all matters. You can have 36 rabbits in there - like even Facebook does now - and nobody will care.
Not everything VCs say applies to everybody, don't take their guidelines as gospel. They're more interested in finidng specific types of startups that fit specific parameters, because it serves THEM to do that. For example:
They kept saying VR glasses, then they kept chanting crypto,... now the fashionable thing to say is "don't do social". The fact is they (potential investors) have no idea what the next big thing is, and don't particularly want to know. They'd rather do "now big thing" and cash out at an upcoming round than take a thousand "next big thing" chance when all of them could bomb.
Also, I don't think text vs video is about generations so much. Twitter is not for people who like to read/write text, it is more for people who like their own opinions. Similarly Insta is for people who like their own face/food/fitness and want to share it.
Point being, it doesn't matter one rabbit or a dozen. More relevant question is, can you make users stick and come back? That's what it boils down to.