@Karen2913 No review doesn't affect you in any way. It's good to see reviews from repeat customers, as it shows people like it enough to come back, but if they are going to tank your ratings, then no review is better.
I do agree that maybe these guests just need a bit of educating. Airbnb tells guests that 4* s means "good" so most guests think they are giving a rating the host would be pleased with. If they are repeat customers, they certainly have no intention to do you wrong, they just don't know how ratings affect hosts.
But you have to be careful how you approach this. If it feels to the guest like you are pushing for a 5* rating, it can be offensive and backfire. But I have had review discussions with guests in my home share, which just let them know that there is hypocrisy in what Airbnb tells guests and how they apply those ratings to hosts.
My guests have been shocked to find out that Superhhost status is lost if the rating falls below 4.8, and that Airbnb warns hosts about ratings lower than 4.7.
And yes, as others have advised, you can deal with repeat guests you like off-platform if they're okay with that.