Was there a policy change or what?

So I have now gotten a 14 day suspension. From chats logs that are post game. And not even post game lobby but private messages. From someone that sent in a ticket(they added me after the game and harassed me when I hadn't done/said anything particularly nasty enough for a 14 day in game. During this harassment they sent me the link to the ticket). Now I'll admit yes in the private chat I was toxic(only in return here). People that add me after games wanting to s*** talk really get on my nerves and it was a bad game so i let loose on him IN PRIVATE CHAT. Now flashback to October 1 2016, I have a ticket that I submitted over another player harassing me quite heavily post game in a private chat. Using a lot of really awful terms. I submitted a report post game for their behavior in game and then submitted the ticket after they harassed me. I got a response from Riot FunderFaker saying that because it was a private message they can't do anything. Sooooo. was this a change in policy? Cause I feel either I was lied to or something. For that matter if you add someone to shit talk them expect it back. Why does anyone get punished in that situation? If you can't handle what someone is going to say don't go and instigate it. I very well could go submit a ticket right now for the things this guy said just yesterday(when it happened) but I didn't because I was under the impression even if I wanted to(I was being the "bigger" person) it would make no difference.

** TLDR can riot ban on private chats alone now? Cause I was told a year ago they can't.**