I can confirm this. After reading an article years ago about skipping shampoo I tried it for a few weeks and indeed, was fine, so just stopped. Have used shampoo perhaps a half a dozen times in the past 20 years. And I work out (sweat hard) everyday. But FWIW i keep my hair quite short!

Also minimize body soap but can’t do without it. Hands get washed a lot of course but I try to avoid liquid soap (Dr Bronner's is OK) and "purell" if I can.