Link to article on Pete Townsend's first guitar smashing:
https://faroutmagazine.co.uk/the-who-pete-townshend-first-smashes-guitar/
Pete Townshend, the guitarist of The Who, is known for his energetic and destructive stage performances, which often involved smashing guitars. The exact date of Townshend's first guitar-smashing incident is not widely documented, but it is believed to have occurred in 1964 or 1965. Townshend's guitar-smashing antics became an iconic part of The Who's live performances and were seen as a symbol of rebellion and rock 'n' roll excess. He continued this practice at the Monterey Pop Festival in 1967, which served as their first major gig in America. He and Jimi Hendrix flipped a coin to decide who had to follow who in the concert schedule, and Pete won, electing to have The Who play first. Jimi’s set included the iconic burning of his own guitar to end his own set.