Try e-harmony. No one can message you without your approval. No one can even see your profile.

On other sites if you are over 50 and aren’t looking for commitment, you’ll attract players. Probably not sugar mama seekers but guys looking for certain kind of fun. I honestly don’t know anyone over 50 who is looking for casual. Either not dating at all and focus on hobbies, families and friends or having more serious thing in mind. If someone decent uses dating site at our age it’s for a serious thing. Not saying you won’t meet a nice guy on there but honestly it’s unlikely.