I don't think Varane would have suddenly performed better without Ramos given enough playing time. He is already 28 , just look at our senior players who got slapped in the CL several years in a row (he obviously didn't get slapped , but he did drop absolute stinkers against Ajax, City , Juve ? etc.) they have only gotten worse mentally. Then you have the likes of Nacho and Militao who have really stepped for you guys just fine without Ramos. Either way I guess we will see how he will do at Real next year without Ramos or somewhere else.
Edit: deleted my post since you added on to it.