My casual observation is that people's perception of bean's gas causing properties is way out of line with what they do for most people and strongly influenced by people who have unusually high intolerance, who are the minority.
A part of the article that irked me is where he talks about why he's going to ignore people who say you get used to it because he thinks the microbiome change doesn't make sense misunderstands the gas/bacteria process in the gut.
There is a big mix of FODMAP eating bacteria, both inefficient generalists that can eat FODMAP but do it poorly and create a lot of gas, but also specialist bacteria like Bifidobacterium that also eat them but are much more efficient at it and produce much less gas. With more food the specialist bacteria becomes more prevalent. There are also gas consuming bacteria, not just gas producing, which also will shift in population. The idea is not that you just grow a larger population of the existing problematic bacteria.