But the US is, of course, a fairly unique case here. Most people become stateless due to state persecution (famously many Jews were stripped of their German citizenship by the 1935 Nuremberg laws, and many Kurds were denied Syrian citizenship under Assad) or by falling through weird administrative cracks (for example, see the cases of Mehran Karimi Nasseri [3] and Shamima Begum [4]). There are also cases (e.g. many Druze in Israel and the occupied Golan Heights) who refuse to accept citizenship they are offered on political grounds,[5] who would be considered de facto stateless if they do not have another recognised citizenship (though I'm not sure how Israeli citizenship works; the US considers you a citizen with worldwide tax obligations whether you accept it or not).
The interim solution is to get a 1954 Convention Travel Document[6] from one of the signatory states, which functions like a passport (and taxes in most countries are levied based on residence, rather than citizenship, so you'll still be paying them already). For a permanent solution, you'd need to go through the normal naturalisation process to become a citizen of a new country.
[0] https://en.wikipedia.org/wiki/Statelessness#United_States
[1] https://www.vice.com/en/article/a-bum-without-a-country-0000...
[2] https://dollarvigilante.com/2015/07/20/interview-with-glen-r...
[3] https://en.wikipedia.org/wiki/Mehran_Karimi_Nasseri#Life_in_...
[4] https://en.wikipedia.org/wiki/Shamima_Begum#Citizenship
[5] https://en.wikipedia.org/wiki/Druze_in_Israel#Status_of_Druz...
I'm not entirely sure how that works out and which citizenship someone living in Gaza or the Westbank would fall under. In any case I can't imagine that a Palestinian passport holds much value.