Their music attracted far more listeners, I won't say it was MADE to fit popular radio formats but it did. Yes and Genesis, more than the other two, were made for FM, not AM, and they attracted a niche following - a sizable one but definitely NOT mainstream. The Who and Deep Purple had a much harder rock sound that also wasn't heard often on AM radio.
Radio play = sales = money = mainstream. Fleetwood Mac and The Eagles have albums on the Top Ten in all time sales.
Eagles are #1 (Greatest Hits 1971-75) and #3 (Hotel California) and Fleetwood Mac is #10 (Rumours).
The others, as great as they all were (Yes is among my favorite bands), do not have a Top 100 among them.