You are right of course, it depends on the individual circumstances and citizenship, as well as the countries of (temporary) residence. Much harder as an US citizen, or someone with a property, or wife and children that reside somewhere officially.it's quite easy to become perpetual traveler however way more complicated not to be seen as tax resident (anywhere)
But fortunately it's not impossible, and of course it's easier if one doesn't run a business at all, stays away from US/EU, and has no need for bank accounts or brokerage there. No business -> no income -> no tax.