Can we really get sued for writing a bad review?

With the recent court case in mind, where a French food journalist was sued successfully for €2,500 by a restaurant for a bad review, it struck me as a warning shot across the bows for all on line reviewers.
It poses an interesting conundrum simply because of how Google handles search results.
In the case of the food journalist, her headline was the culprit;  it was about an Italian restaurant called Il Giardino and the headline ran "The place to avoid in Cap-Ferrat. Il Giardino."  It seems Google placed it very high under Cap-Ferrat searches and caused business at the restaurant to plummet. it didn't help of course that she called the boss a "diva" which under French libel law is an insult.

Nevertheless, under normal circumstances any review has to be simply seen as a personal opinion, however Google has become so intrinsic to finding information online, it is quite possible for something like this to happen over and over again.
So what do we do? Should we include large swathes of legalise at the bottom of each review? Should we all take legal advice before publishing anything? How about filling the review with middle of the road non confrontational phrases?

And why stop at food reviews, the same goes for hotels,  films and shows. Could we get sued by a hotel interior designer because we didn't like the decor?