While I agree with some points, the wedding was real. I believe the private wedding PC told Bojack about was just to let us know that, while Judah and PC are still wrapped into their jobs they both were always extremely committed to, they made time to have a private ceremony so they could both get away from all that, which still shows progress for each of them as well as them as a unit.

Todd, Diane, Mr. PB etc were all there because that’s what they do. Even if it was moreso for the industry and as a career boost for PC, it isn’t at all hard to understand why all of her friends were there from a logical standpoint. It also isn’t too hard to understand why the characters would all be there from a TV show standpoint, because the writers/ show runners wanted to wrap things up in a ‘pretty enough’ bow.

Judah not being there isn’t even really off character for him. Judah takes care of the business end of things but isn’t a very social person, so it makes sense he could leave that part to PC. She thrives at social gathering, Judah though? Not so much.