Senna isn't the best because he died young and while he was still racing, He was highly competitive while driving inferior cars, he was the one that drove in the rain like no one else; everytime it would start to rain he would be the one setting the pace, taking the car to a new limit (running seconds bellow his opponents). He was the driver that has the highest amount of victories in Monaco by far and still has one of the best win/race and pole/race ratios. Senna was a champion when F1 was a driver's race and not a high technology computer/tire competition. Nowadays drivers are more like passengers...
I had the privilege of watching Senna three times; all of them in Interlagos, Brazil. Including his very last race in his home country, racing for the Williams team. But by far, the best race I've seen in person was his victory in 1993 showing the favorite with the much better car, Alan Prost, who was the best driver. After the race we all (on the crowd) made our way into the track... it was great!
I highly respect your opinions though!!!
Jim Clarke was a great driver and so was Juan-Manuel Fangio!👍