My partner and I live on a boat and our water comes from an 1800L tank. To save frequent trips to the water point (a half day job), we have become a lot more mindful of our water usage. We now probably wash every second (sometimes third) day, unless of course we are doing really mucky, sweaty stuff. I used to be someone who couldn't really wake up without a shower and would feel kinda gross without my daily one, but now it doesn't bother me at all. It's interesting how you adapt to changed situations.
I think if your body, hair and skin is repeatedly washed with soap and water, it works harder to produce more oils to keep everything supple and protected, get oilier, need more showers etc. Stop stripping it so much, body adjusts over time. I have definitely noticed my hair and skin is less dry and in better condition since reducing the washing.
We don't smell on day two, if anything we just don't smell of soap, I guess on day two we smell like a human? We also spend a lot of time with other boat dwellers who are also pretty similar in their approach to water, and they all smell pretty normal too. Although now we are all starting to smell like woodsmoke as the burners come on!
And this is not all us boaties just being crusty hippies who love our own fart and BO stink, I also spend time with non-boat dwellers and apart from the woodsmoke there is no difference in smell. And believe me, my pregnant super nose is picking up everything, there are some serious non-clothes washers getting around out there which have been regularly gagging me out on public transport!