it's not that only one type of playing is the only good type. Hendrix was sloppy and Page was as well. sometimes you can call it loose, and those types of players are often adventerous in their playing. Robin is sloppy too. some think he can barely play. others praise his style of playing.
Slash had a rare balance between tight and loose back in his peak. Now I agree it's different, maybe more mistakes. I thought this performance was great, but for me it's the overall vibe of the performance.
I also think Slash took what Jimmy Page was doing and made it tighter and added his own thing to it. If you like more accurate playing and it's one of the factors that is important for you, that's fine. but like EVH said, there are no rules. (Eddie wasn't really into Hendrix because he thought he was too sloppy, depends on what you prefer as a listener) look what Zeppelin achieved with Page and what Jimi did with his choice to throw caution to the wind and just play in the moment.
none of this shit is an excuse as there were players like Jeff Beck who had everything but sometimes, maybe often, he also crashed and burned in live performances cause he was pushing himself beyond what was comfortable to play.
a big part of guitar playing in the genre of blues for example, the style and personality of it is the little imperfections when a player bends a string, you can call it out of tune and when you're playing isn't on time, a little behind or a little ahead, that also gives it its own thing. sometimes its sounds bad, but you don't have to play an instrument to know what you like and what you just don't give a fuck enough about if at all for it to ruin the experience for you.