WiFi can be easily interfered with so you test wired and the WiFi off in the router first.
I have recently been noticing some lag spikes every here and there while playing games. When I say here and there, I mean me not being able to move for five seconds. This happens probably every 45 seconds. It has made games completely unplayable. My download speed is below and as you will see it is pretty high. I have a NETGEAR A6100 WiFi Adapter. While you might be thinking it is that, I am pretty confident it is not. A few weeks ago I went on a cruise for a week. Everything worked perfectly when I left. No spikes. And no more than 50 ping on any US East server. However, when I got back I hopped on Skype and started talking to a friend. All call audio would stop and pick up after about five seconds. It would not repeat what they said so I missed 5 seconds of a sentence, which could take up the entire sentence. I can't even play Brawlhalla without walking off the map on there screen. But on my side I'm trying to hit the opponent then teleport into the abyss.
Speedtest.net results : https://gyazo.com/62b6aa7e412a5d85f2cc430b517ad029