That is the argument some have given up to stop the leaderboard as those who win that every month are the most dedicated.
There is no singular good way, apart from prizes based on judges, talent, like photos, meaningful discussion, etc. The admins do those too. So the genuine and well intentioned folks will eventually win something anyway. e.g. your photo this week.
I’ve been on the Internet, dial-up bulletins, Usenet, before some here were born, and there’s little you can do about it. e.g. if they stopped by IP then VPN solves that.
I’ve had to travel the world and I’ve had to use VPN to get around national restrictions. The Chinese know that issue quite a lot.