Dxc did the same last year: a sudden spike in extreme ‘good reviews’ in the space of 4 weeks from the same areas that spoke in general terms and used Similar language.
Because many people write a review after they leave a company, you'd expect a surge in reviews after a large layoff, but you would also expect them to lean to the negative side. (Although, it's perfectly possible to be laid off from a great place to work.) But a flood of positive reviews is a pretty good signal that there's a problem.
If it's either the worst place in the world or the best place in the world, someone is not telling the truth. If there are extreme views, either someone probably has an ax to grind or someone is pressuring people for good reviews.
Be wary where the reviews illicit the extremes. We apply the same psychology to amazon. We would rather buy a 4 star product with lots of reviews than a 5 star product with fewer reviews.
If it sounds too good to be true, it probably is. If many people repeat the same talking points, there might be a problem. You can see this pattern in the 2018 fake reviews injected for DXC UK Chesterfield and DXC Newcastle of which the reality Was somewhat different with Chesterfield on the verge of closure.
Of course the honesty is gleaned from colleagues after a new start joins the company and if the expectations are vastly different, that can also leave a bad feeling and a negative review, as has been the case here both on here and on glassdoor where many newstarts regret their decision to join, because there is no work for them or they have found themselves at the back of a queue of layoffs.