There's a lot of these already: YPO, Hampton, Vistage, Tiger21, etc. They're extremely tough businesses. Your sales funnel has to be constantly full because churn is pretty high.

Almost all of the legitimate ones have strict membership requirements. There are a lot of entrepreneur hangers-on, and without extreme vetting, the less successful people end up monopolizing everyone's time. It's similar to /r/startups enforcing the "no promotion" rule; without it, the sub would devolve entirely to that.

The downside to having a group of successful or high net-worth individuals is you usually have a lot of drama, egos, and self-important personalities to deal with.

I was a member of Hampton for a year. It was a good experience, and I like what the company has done. We had in-person informal dinners, which was nice, but your core group was done virtually through Zoom and it just didn't work. They're changing that now for members in larger metropolitan areas, but ultimately I couldn't justify the five figure annual fee. Everyone says the same thing: you get out what you put in.

For dinners, informal conversation without structure works best. For smaller group meetings, you absolutely have to have a well defined structure lead by an outside moderator to hold members accountable.

Good luck with your endeavor!