I'm actually on the fence concerning the 365 GTB/4 & GTS/4 being a supercar. I love them. I have always loved them. I would love to have one. But is it a "supercar"? I don't know. I sort of put it in the same class as many other beautiful cars. For example, the Jag V12 XK-E or an Aston Martin. If it were 1971 would I have a poster of a Daytona or XK-E on my wall? Maybe - probably - but I'm not sure. I suspect the Miura would have definitely been on the wall (along with the Led Zeppelin posters), and the Daytona would probably have been the there too. The XK-E, probably not.
Odd, when Enzo himself referred to the E type as the most beautiful car in the world. The 6 was a better car, by miles.
Need to define supercar. My definitition would include but not be limited to Exceeds all performance of it peers by an order of magnitude".
The Countach I exclude easily on the handling issue. The Miura for similar reasons. Both were exemplary exotic, but that in itself does not really a supercar make in my eyes.
The GT40 certainly qualifies on all counts and you could order one at your local Ford dealership so I tend to bend on that one. However, you would have to include the MacLaren MP6 for similar reasons, even if the dealer you had to order it from would have been Bruce himself.
The Daytona, once again exotic yes, super, no.