@Anita993 As others have said, property management companies, or hosts who have a lot of listings and high turnover tend to leave uninformative generic reviews, like "Nice guests" or Great guests!".
I'm not sure why you think it's weird or suspicious for a guest to have reviews from a few years ago and nothing since. The majority of people iin this world can't afford to travel on a regular basis. They may save up for a trip somewhere and then not go anywhere for years after that.
You can do a little deeper sleuthing by clicking on the hosts' profiles who left those reviews, then when their profile/review page comes up, click on the profile photos of other guests who left them reviews to see if the hosts leave those generic reviews for all their guests.