It quite literally hasn’t. The only thing it can’t be used for is reports on cheating, bots and unsportsmanlike conduct. Those three have to be reported using the server replay function.
The in game complaint system works perfectly fine and the reports from it are very actively actioned when they are made on the correct things, i.e any content in chat that break the rules and bad names that are against the rules.
Please read the link i sent on what function to use for what issues.