I read theory a lot and I can see it as an argument that the filing process for Americans with reasonably simple situations are painful and difficult (ie that there’s no government website[1] to file for free, or that the IRS can’t fill in details for you). But I would think tax companies are not hugely important in the grand scheme of things and that the actual reason that tax is so complicated is more broad, eg:

- many layers of taxation due to the political structure of the US – federal, state, city, county, maybe also school/water board?

- lots of different deductions exist, and probably for any deduction there are politicians who want it to stay. Each individual deduction may be well meaning (or the result of fraught negotiations) but the whole is undesirably complicated and hard to fix. The rich also have an advantage in a more complicated system but AMT was created so presumably this advantage has limits.

While the first point seems to somewhat naturally fall out of the US political system, I don’t have a great explanation for why the second should apply in the US but not other countries? E.g the U.K. tax system has a few special cases (something to do with child care, some married couples things, some ability for farmers to carry losses forward, maybe some special rules for reverends or Lloyds underwriters?) but nowhere near as many as the US. I think both tax systems are quite old but maybe some U.K. government in the 20th century decided to simplify it a bunch? Certainly a bunch of old taxes like rates don’t really exist for individuals anymore.

[1] presumably the US government have been terrified of launching big websites since healthcare.gov too.