Try a full reset first. There should be no addons, outdated or not once you complete this.
This is only a diagnostic tool, not a fix-it. Ran during when lag is the worse can point out where in your connection dropped packets occur. Usually anything in Blizzard’s network is monitored by them.
When is the lag occuring. Are you doing instances/queued pvp. You could be on one server, but for group content depending on time of day, could be connecting to a different one.
Where are you connecting from? What kind of internet?
80-200 is in my opinion not unusual. 400 might not be either depending on where you live, and what servers your connecting to. Not ideal obviously.
There may be a lot of distance, and routers, between where you live and Blizzard’s servers.
You can post your trace is you code block it, try: