@obj noted in another post here that MLAT positions travel by UDP and ADSB travel by TCP. The TCP should be more tolerant of congestion and interference, but I recently relocated my WiFi router (twice) and noticed first a decrease and then a bump in position and aircraft stats.
We had moved the router to a worse location as part of a minor remodel and I had noticed a decrease in positions but very slight. I was also getting occasional dump1090 error messages when viewing the PiAware web page so more indications the signal was poor. There’s three of us in this area that were trading off on top position reports and I dropped enough that my station was no longer trading that off with them. My wife was also having spotty connect issues with her devices so that prompted the move to a much better location.
I hadn’t checked actual S/N on WiFi for my PiAware station until the last router move but S/N is now great and I’m back to trading off top spots in this area.
So even with error correction under TCP I think I was still dropping data packets that were to be sent to FlightAware due to weak WiFi and possible congestion on the channel. In the new WiFi router position I was also able to use wired connections for more devices to lower some traffic over WiFi. It wasn’t an especially big change but definitely made a difference in position reports and rankings.
So WiFi S/N appears to be a possible factor in position rankings especially if you are seeing dump1090 error messages.