I play the guitar and would consider myself a late stage beginner, on the cusp of being an intermediate player. What many people don't realize, is the guitar is a young instrument. First "modern" accoustic guitars appeared in the 1830's and the first electric guitar in the 1930's. The guitar and guitar players are still evolving. Top players today are as a whole better players than their predecessors, however special musicians have emerged over the years that really moved the instrument and music forward. We stand on the backs of these musicians.
I vote Jimi Hendrix, as much of what we know as rock music doesn't exist without Hendrix in my opinion. Give someone like Hendrix modern tools and access to the vast history of styles and techniques, and he'd be a modern master too is my guess.
Here's some players I've been listening too lately and a song worth a listen.
Billy Strings- Turmoil & Tinfoil
Marcus King- The Well
Tommy Emmanuel (been around a long time but not well known outside guitar world) Lewis & Clark
Isato Nakagawa- Ramon no Ki
Calum Graham- Tabula Rasa
Ernesto Schnack - any of his Tool covers on Accoustic are killer good. Forty Six & 2
You can't count out the Beatles and what they were able to do with their guitars. They were not the fastest players, but they came up with incredible hooks and melodies on the guitar parts in their songs. They were creative enough to influence so many others, including Jimmy.