Fair question IMO. Of course trailer parks are (hopefully) always among the most affordable housing options. However, living in one should be a choice of the

Fair question IMO. Of course trailer parks are (hopefully) always among the most affordable housing options. However, living in one should be a choice of the individual, and the fact that there is a notable population in these places tells me that these are not exactly free choices à la "I shall live frugally" but rather a systemic problem. So: "acceptable that trailer parks are more than a mere curiosity of vanishing proportion in the story of housing in the US in 2021."