A good friend of mine who I help with YouTube videos is a broker. He rarely pays attention to reviews, but we're in a smaller town and even having just a few provides the highest rating around. However, this is obviously not the case in more competitive cities.
If there's one thing I've learned about online marketing with my broker buddy, it's that it is important for him to be everywhere. He's on Zillow, Realtor.com, Loopnet, YouTube, blogs on his site, and, of course, he's on Yelp. Well, I've also learned that having more inventory helps as well, but of course not everyone has 50+ active listings at any given time.
Real estate brokers and agents in more competitive cities do rely on reviews, and one of the places they receive reviews is on Yelp. Indeed, Yelp is more popular for cafes and restaurants, however all businesses use Yelp reviews, and search engines such as Bing and Yahoo display those Yelp reviews. That's why all real estate agents with a Yelp presence should be aware of The Yelp Review Purge of 2018.
I'd encourage you to read the above referenced article. To make a long story short, Yelp has suddenly made a drastic change to the way reviews are displayed. "Recommended review" counts are way down. Some real estate agencies are seeing a 50 - 75% reduction in recommended reviews. I believe Yelp is filtering positive reviews. That's based on a phone conversation a client and I had with them. I also dug up a tweet where they stated that positive reviews may set off their filter.
Anyways, as we go in to 2019, it's a good idea to obtain as many reviews as possible in as many places as possible. I just purchased a second home myself, and I can tell you, as a client, that I do look at real estate agent's Zillow pages, and the number of recent sales, total sales and review numbers are indeed important to me. I do not personally look for agents via Yelp, but some people do, and the new algorithm is something to be aware of.