Eh, I thought it was a good article. He pretty clearly labeled the breakdown as the "basic" expenses associated with maintaining his current lifestyle. He's just in a sweet spot where his retirement hobby is a business that makes a ton of money, thus allowing him to buy things and expense them in the interest of research. But all that stuff is optional and could go away if the business did -- and he even (fairly) acknowledges that this might displace some of the desire for travel/stuff he might otherwise have. IDK, I really don't know many people at his level of income who still maintain his type of lifestyle.
It is an interesting corollary, but my mom just retired from teaching after almost 40 years. Except she still has her second job, a/k/a the consulting company that she co-founded probably 10 years ago and that makes her more than teaching ever did. And, like MMM, this is her hobby -- she loves what she does and will do it until she dies. She cracks me up, because she was telling me that her expenses last year were $30K -- most of which is taxes/utilities on three properties. It is absolutely, completely true that she has a travel bug, and that her business satisfies a lot of that need (she travels almost every week). So in the absolute sense, she actually spent a lot more than that on flights, hotels, and restaurant meals. On the other hand, those expenses are a necessary investment to earn a low-but-multiple-six-figures net profit, and if she shut down her business tomorrow, all those costs would go away -- sure, without the job, she'd probably travel more frequently for personal vacations than she does now, because the business travel scratches the itch, but there's just flat-out no way she'd travel or eat out *that* much. And when she's home, she's puttering around the house, shopping at the Asian market, working in the garden, and basically still being the fundamentally frugal person she has been my whole life. So I mean if she weren't working, she might spend $40K vs. $30K, but I can't see her even getting up to $50K.
I get the same impression from MMM: he seems like the same guy he has always been, just with more cash to play with. He has fun letting the business play with it some, but he knows better to wrap that into his basic lifestyle expectations.