... this has never been up for debate though. You are literally arguing an entirely different subject now. The discussion boiled down to why it matters what people do with mods on their own screen. Putting your example into gameplay context, people who mod their game are not going to care whatsoever whether your character is well dressed or wearing baggy blue jeans. They aren't likely to bat an eyelash towards you one way or another. Likewise, without prior knowledge that particular person has a mod run, you will also be none the wiser. An equivalent is, once again, if someone were to imagine me naked while I was talking down the street. I can't control their thoughts nor does it matter what types of clothing I'm wearing. If they want to imagine me naked, they will. Mods occupy a similar space, except as stated, modders generally aren't interested in anyone else but themselves.
This is what prompted accusations of people being overly sensitive, especially since the OP went out of their way to join the very discord where all these mods exist, knowing it was going to bother them.
I sincerely hope you realize this post, were it taken purely at face value, depict Square Enix and the FFXIV development team has wholly incompetent at even an amateur level.
ACT does not work the way bot programs do. The former simply reads data relayed into the chat logs. Were that information made unavailable, ACT cannot parse. Bot programs, meanwhile, prompt script to play the game for you—something ACT cannot do. In crude terms, parsers are little more than live calculators. If getting around these things were as simple as you make it sound, piracy and ad blockers wouldn't exist. Facebook boasted the same rhetoric you have—claiming to have beaten Ad Block. They were made to look foolish in two days.
Could they attempt to block ACT? Theoretically, yes. It, however, would garner an immense amount of backlash, and change little as people would make alternatives.