hell, I shower once a week, when I’m not doing manual labor like, say, construction or weightlifting. (which I then shower immediately after.)>
I don’t smell at all by day 6, but my hair gets mildly greasy, so I wash it.
live at 6273ft above sea level, in a “high desert plains”, acccordig to google.
YMMV, obviously.
worth noting that I’ve also been noseblind since birth, and the only feedback I have in my scnents (or lack thereof) has been my family’s noses, and my partner’s nose.