The Sex Pistols formed in 1975 and broke up in early 1978, and are seen as the first of the Punk Rock bands. The Clash formed in 1976 and credit the Sex Pistols.
I very much consider some of The Who’s stuff (earlier than ‘75) Punk Rock. Maybe calling them proto-punk would be accurate.
Sounds right to me since there was no genre called Punk during their first 10+ years. Those bands that actually were called Punk never did anything for me.