That logic makes no sense.
You're saying that is ok to completely ignore the fact vast majority of reports are just out of spite and has no factual basis. Those *action* are taken by automated system, for example I can report anybody I don't like or just for the fun of it. Actions taken will not depend on his actual behavior but the fact how many friends I can call to report him too. With that logic let's replace all courts with just popular vote about every accused.
Even spam reporting will not work, at least in LoL. It takes many votes to end up in the Tribunal. All final decisions are reviewed by Relic. THose that abuse the Tribunal "punish" feature will have their privileges revoked, Having a basic report system is better than having absolutely nothing