Why is my wi-fi connection so slow?

I am using an iPhone 12 Pro Max. I recently noticed that my video streams were buffering. I have fiber internet service provider with up to 1Gps download speed. When I run the internet speed test on my phone I get 1.4Mbps. The same test on another my Lenovo tablet gives me 160Mbps. Something happened recently that caused this but I am not sure what. I did apply the recent iOS 16.4.1 software update.