I only tested it on a few devices, but I saw the speed drop on my PC, work laptop(a dell), two iPhones, and a PS4. Only device that I couldn't get to drop speed

I only tested it on a few devices, but I saw the speed drop on my PC, work laptop(a dell), two iPhones, and a PS4. Only device that I couldn't get to drop speed was my iPad. I literally spent multiple evenings for 2-3 weeks running as many tests as I could and was never able to pinpoint it to anything specific. During my tests, I found a few reddit posts of people experiencing a similar issue. A few people were linking the issue to a firmware update around November/December of 2018, but I couldn't verify since I bought by Wifi device around February of 2019.