I can only speak to the personal part of this and will stay away from the political. But the fundamental concept here -- that MMM has identified the best way to live, and that everyone would be happier if they could disregard consumerism and embrace stoicism -- is just flat-out wrong.
What you have here is selection bias in operation: this forum is filled with people who identify with Mustachianism and have found it compelling in their own lives, to greater or lesser degrees. And because people here are naturally drawn to Mustachianism, it seems inconceivable that others wouldn't also be happier if they could just be exposed to it and convinced to give it a try!
Yes, this is very true for many people. But not everyone. People have very different drivers. I happen to know quite a few people who are not at all Mustachian and yet who have led perfectly happy, productive lives.
My boss: millions in the bank, kids launched, he even thought about retiring a few years ago. Then his wife opened a restaurant, so he recommitted to the job just-in-case (note: restaurant has been a huge hit, so not necessary). But the firm has had a few tight years, and he is now completely recommitted to the job, because the firm matters to him, and he wants the people he "raised" to do well and the firm to succeed long-term. This is also true of almost our entire older leadership, btw. They could all retire comfortably. They stay because they enjoy the work and care about the firm.
My dad: worked for big company, bought his first Porsche more than 30 years ago, has never been without one except when he was overseas. He *loves* his car and loves expensive travel -- total spendypants. He is retired on a pension and a little savings and could choose never to work again. But he still consults periodically so he can keep paying for the extra spendy stuff that he enjoys so much.
Me: Yes, I am here, and yes, I can use more stoicism in my life. But I never, ever, want to live MMM's life. I grew up poor. I did everything for myself because I *had* to. I don't find joy and freedom in cleaning my own house and figuring out how to make do without spending money on anything, because I lived that way for my first 25 years, and I worked my ass off to escape that life. [as did my dad, btw -- see the common theme there?]. So I have 100% embraced MMM's philosophy of putting FI above consumer goods, because my #1 driver my whole life was to never be poor again. And I could retire now if I wanted to or had to. But, dammit, I like my convertible -- I get visceral joy from driving with the top down every time. I like my house and my neighborhood, and I am proud that I worked hard and saved hard to be able to afford it. I am not willing to give up these luxuries, and doing so would not make me happier -- I know, because I have lived the other side of it. Every day I drive that car, every time I come home, I am reminded of how fortunate I am to have this life, and how much I have accomplished to be here. At this point, I am getting tired of working and some days just want to bail; but then I still work for people like the guy above, and something happens and I am reeneegized again. So for now at least, I am still willing to continue to work a few more years to ensure I can maintain my current lifestyle for as long as I want to. And if the day comes that I am just done, well, the good news is I have plenty of luxuries I could easily cut.
To me, the fundamental tenets of Mustachinaism that I find compelling are the realization that the power to shape your own life is in your own hands, largely based on how hard/long you want to work and how much you save, and that your spending should be intentional and focused on things that are meaningful to you and bring you joy. And those answers are going to be different for everyone. I have shaped a life that I am pretty damn satisfied with, and if it no longer fits at some point, well, I'll change it again. But I'm not going to change it to fit someone else's version of "happy."
Tl;dr: it's rather egotistical to assume that you know what will make someone else happy better than they do themselves. People tend to be more receptive when you arm them with information and then trust them to make their own choices.