Of course he thinks that he as to. As others have pointed out, he's making $110k a year and not happy with how much he has, it's pretty likely he's spending too much, or he just has unrealistic expectations.
> His lifestyle sounds fairly frugal by modern standards
You mean modern standards that set the goal posts we should all own x,y,z ? If you didn't know already, those "modern standards" you refer to are the problem here.
> What does that do for everyone else? Do they all just need to adjust their attitudes and accept their lots in life?
Attitude and spending. And plenty more things too. Read the book I recommended.
> If those goalposts are essential (rent, health care, food)... what is he supposed to do?
If you're trying to say for one second that someone making $110k a year can't pay for those "essentials", you're not being productive here.
Let's go with the case of someone earning $30k who's can't afford those - which I think is a realistic scenario. In that case, then the only option is to adjust ones expectations and personal goal posts to fit reality. Hypothetically, if the economy completely dies tomorrow (a la Germany, USSR or Argentina every ~10 years) will you be horribly unhappy you can no longer own your own car and are forced to take public transport, and must downsize your house to a small apartment, etc. etc.?
If you are unhappy with that, then you're basing your happiness on external factors outside your control (the economy) and you're setting yourself up to be a very unhappy person.
Also, he asked about other people and you're saying he needs to adjust HIS attitude? What does that do for everyone else? Do they all just need to adjust their attitudes and accept their lots in life?
The goalposts moving doesn't mean he's setting the goalposts for himself; if anything, it implies the opposite: Someone else is setting the goalposts. If those goalposts are essential (rent, health care, food)... what is he supposed to do?