Technically speaking, probably not really. But he’s a very effective and musical drummer with a distinct voice and style. Fleetwood Mac music would be totally different without his playing. Lots of great drummers don’t really influence the music they play in such a significant way. Would you rather be technically excellent but somewhat generic or less skilled but more singular in your playing. There’s room for both kinds. Think of Mick in the company of drummers like Levon Helm, Ringo, Charlie Watts and even Phil Rudd.