Revenge is Human Nature
A bad review resulted in revenge action? Say it isn't so! But it is so and common, it can also have major consequences.
An example in the USA is the Wells Fargo scandal that included the company blacklisting employees on a "U5" database of financial workers. The U5 database was meant to alert finance institutions to "problem" workers (just those that broke the law of course) and was checked before hiring someone new. Wells Fargo used it to blackball those workers who tried to expose the Well Fargo Scandal.
Recently found out that the move to electronic health records, resulting in a single file on a patient (needed to prevent drug interactions and other medical errors) gives Doctors and other health care professionals a very convenient form of revenge. Should a patient be "difficult" or equally likely the healthcare professional due to excessive work load was not in a mood to receive a negative comment or deal with a difficult personality can feel a little better by placing comments in the file the patient will either never see or only see after it is too late.
Of course that might not just be revenge as it can be used to defend oneself against future malpractice claims.
There are many ways to prevent revenge actions for those wanting to report possible criminal activity, malpractice, or fraud but our laws are written and enforced to best benefit those funding political campaigns or ensuring those in office are well compensated.
That and business has learned from the US government itself that attacking those trying to expose misdeeds is the best first reaction. Until we can get governments that answer to the people, and not our Elite, we can expect little support for those that try to speak out, be it violations of a Constitution or software fraud.