Indeed it is. In the US and everywhere.
Whenever someone in some position under public scrutiny does something wrong, the issue is judged less by the deed itself (the sexual assault that occurred) but by the proponents vs the opponents of public person.
And there are some things to be said about that, I think.
1. Nobody waits for an actual investigation into the act itself. At the core of this is that fact that as a victim, the higher the perpetrator's profile, the less likely your allegations are to be investigated to the point the only option is to jolt public opinion into action. However, once that's done the public takes less than a second to already pronounce the matter. He's guilty or he's not guilty are two camps and the next step is governed by which camp is louder.
2. There's exactly 0 incentive for someone in Cuomo's position to say "I did it, I'm sorry" and continue from there and 100% incentive to deny and struggle forward until the public says 'no'.
Thing is, once something like this comes out in the open, the details don't matter. The legal definition of the act doesn't matter. Sexual assault, sexual harassment and so on, all lead to the same expectation from the public: that as a perpetrator you quit whatever it is you were doing and leave the public sight never to be seen again. There's no avenue to acknowledge and atone for what you did and still move forward with everything else you were doing.
The only option that a perpetrator has is to create a narrative that emboldens supporters and creates legal options (if the case gets too much attention, you have options to have a potential trial taken to court somewhere else, create grounds for dismissal, etc) and power through on the wings of polarization to stay in whatever position you had.
Should he resign? Absolutely. But I doubt it will happen.