OK its controversial, but I need to ask the question what does it actually tell you about your ability to make a QSO.
I would argue not a lot, sure its a fantastic tool for telling you how antenna A compares to Antenna B or what are the best times to work country x. In many cases the ability to work Australia on 1w is not going to be reproducible on SSB, or even on FT8 in many cases.
So the question is does it set unrealistic expectation that people can work great DX on a very poor inefficient antenna with a 5w radio. Possibly
Anyhow despite that I wanted to have a play with WSPR once again, but I would only limit myself to 50mW. So what could I “work”
OK so in the next test I turned the power down to 20mW
Lastly I turned the power down to 5mW and was received in the following locations
Lastly I decreased the power to 2mW and received the following locations
So back to my question, if your running WSPR to simply tick of DXCC then its quite easy even with a miniscule amount of power. If you really want to find out how good your antenna is why now try 2mW, and then compare how many stations can spot your signal over 1,000 KM
Station setup IC705
Power measured using a Oak Hill WM2 power meter accuracy better than 5%
Antenna doublet, fed with 300 Ohm ribbon and 10m per leg