Generally giving the recruiter your opinion of the company will not do much. But if they keep hearing the same reason from many different candidates, to the poi

Generally giving the recruiter your opinion of the company will not do much. But if they keep hearing the same reason from many different candidates, to the point where it is affecting hiring, they might react in some way. If you're not taking the job anyway, you don't have to worry about their opinion of you. But be polite and professional in your criticism.