whereas some person with domain knowledge and a little coding skill will produce something equivalent but actually useable

Yes, that is one of the reasons why I don't have a problem with someone using Excel to do some complex piece of automation: it may take them less time to learn the automation aspect than it would take a professional programmer to learn the domain well enough to start the project. Matlab serves a similar purpose in the scientific community. It's also why I'll weld basic shit around the house instead of hiring a professional.

The problem is when people (like this author) equate someone banging out a spreadsheet for a specific purpose with someone whose job it is to program, declare them all "programmers", and try to use this expanded definition for their own socio-political purposes. Just like how anyone who ever played a game on their cell phone while waiting for the bus was all of a sudden a "gamer" so certain people could declare "half of all 'gamers' are women" and push for "diverse and inclusive" games.

No doubt this expanded definition of "programmer" will be used to beat the professionals over the head with similar initiatives with the goal of making the industry feel "inclusive" to the Excel warriors.