First of all, set your PS4 to block all PSN messages from folks not on your friends list. (Some doofs will overcome this by spamming you with friend invites - you can similarly block that.)
Second, manage your OW settings so you’re not in Team or Match text chat. Do not auto-join team voice chat. There’s never anything good in there.
Third, you have to have quit 4 out of your last 20 matches to trigger the penalty. If you’re leaving 20% of your games, that is excessive.