No. If the system is truly anonymous, then people outside the team can submit reports. Continuous accumulation would not indicate there is probably a problem with the accused, given the motive and opportunities for abuse of the reporting system.
Elsewhere in this thread the difference between anonymous and private is discussed, along with semi-anonymizing strategies for achieving privacy protection, which I believe would be helpful for the outcome you describe.
I wish this was hypothetical, but I once worked with a person that had 3 individuals over 2 years fired for this. Eventually they went too far and HR had to come to grips with an obvious mental illness being the root cause. This person was a great engineer and a good friend, which made it even harder for me and others to admit to ourselves the delusional nature of the claims.
citation please
This was ultimately the pattern at Uber, it was the pattern at Fox News, it was the pattern in Hollywood.
Someone receiving exactly 1 report is probably not a problem. Someone who accumulates reports continuously as team members change probably is.