I've seen Eric Clapton, Jeff Beck, Alex Lifeson, Steve Vai, Frank Zappa, BB King, Andres Segovia and many other guitarists play live over the years.
The only one that rivaled Stevie IMO was Jimi Hendrix. (although sadly I never saw him live ... a bit too young!)
That is a fine list, and most likely most of those performance went recorded, so those in the crowd(like you

) witnessed something special.
The live performance is where the solo act can show their musical moxie by making "adjustments" for the audience.
Many of the finest musicians in history had the talent to improvise. Mozart sure did in his concertos, and for his friend Siegmund Haffer in the violin concerto section of his Haffner Serenade(movements 2-4). Those who bore witness to his play are a blessed bunch.
Beethoven too, got his foot in the door first with his ability to improvise on the piano; the reports preserved by history indicates he was top tier.
Thankfully, many old live performances of JoJo are on youtube and after evaluating them, she's one of my sacred cow musicians, and as you've already read, I compare her to these old classical titans.