No alternative WiFi exists with the identical name. file:video-output-F39CCE42-D05C-4E98-8B59-1241DC238C59.mov
Yes, you can install the router higher on the wall for better coverage and aesthetics.
Reasonable for the size, but the drop-off here isn’t surprising for the OnePlus 7T.
You need to recognize there are many elements affecting WiFi performance, and each device will experience different results. It's impossible to provide a clear, definitive answer. The speeds mentioned were, in my view, reasonable.
I wouldn't anticipate it, though it isn't exactly out of the ordinary either and seems improbable to repair. From my own experience (my WiFi Access Point is mounted on the ceiling for minimal blockages), my Galaxy S10 can achieve 800Mbit on an 80Mhz channel under good conditions. Currently I'm only reaching 700Mbit, sometimes dropping to 500Mbit even in the same spot. My laptop manages 800Mbit on a 160Mhz channel, though on particularly strong days it reaches 1.8Gbit. The issue lies with each adapter being unique—some handle interference better, others have antennas positioned differently, and some use superior antennas (especially phones, which are surprisingly effective despite their size). WiFi feels like black magic; it's remarkable it functions at all. I can personally confirm this because I've been using WiFi since 802.11b, where connectivity was extremely limited.