The flip side happens as well, especially with hotels on sites like Trip Advisor. "My $200 room in Manhattan was tiny and looks out on a light well." Umm, welcome to NYC!
If you're vacationing to NYC from Kansas for the first time, you might book the largest affordable room in the city and be shocked at how small it is. Conversely, if you are familiar with NYC and travel to it enough, you might recognize that a 400 sq. ft. room for $200 a night is an astonishing bargain.
Both types of review are valid, but the former is more valid for new-to-NYC vacationers while the latter would be better suited to those who are repeat travelers or people people who have migrated away from NYC and are vacationing home.
The complaint though, is that there's no way to distinguish between them. How big is big? How small is small? Reviewers seldom list the square footage, and the net result is that one person's anecdotal evidence is countered by another's opposite anecdotal experience. At the end of the day, unless there is an equal number of use cases, we're left reading reviews for context, which renders the star ratings useless.
I don't spend a lot of awake time in my hotel room when I'm in NYC. But my point was that if I have a cheap room in NYC (and $200 is quite a cheap room) my expectation is that it will be quite small.
I actually often stay at a hotel that has small [edit: 170 sq. ft] but deliberately engineered for the size rooms and I rather like it.