Even the examples they give aren't of 2+2 equaling 5, they're of 2.5+2.5 equaling five. Did they even make it past the fourth grade?
It's like they don't even understand their own examples.
--- non-spergs are encouraged to skip down to the TLDR at the bottom ---
Someone who actually cared about math could easily make this a valid example, like so:
"All real world numbers have error bars around them, because it's impossible to perfectly accurately measure anything. One common and reasonable way to round numbers, is to round anything below 0.5 down, and anything 0.5 or more up. So if you have two values that are each bigger than '2' by a little bit, let's say they're each 2.4, then that's still pretty much '2' if you have to round because you can't measure or record the fraction. But if the actual values are adding up in the real world, then you get 2.4+2.4=4.8, which is way closer to 5 than it is to 4. So yeah, 2+2=5 can happen in the real world, but when it does you just say "oh, there's a precision problem here".
The thing is, by this understanding it's reasonable to say 2+2=3 or 2+2=4 or 2+2=5 for various actual values of '2', but you can say with reasonable certainty that if you get 2+2=7 something fucky is going on.
(Of course even then, you could have a number ring or a metric on a non-euclidean geometry that overloads the '+' operator or whatever! Buuut, even then you will still have *some* mathematical system that can describe why 2+2=7 in the circumstances given. Math works, bitches!)
--- TL;DR ---
Yeah, 2+2=4 is "standard arithmetic", and there are non-standard variants where 2+2=something else. But they are STILL MATH. You can't escape the fact that you basically have two choices:
CHOICE A - Words mean things, and once we accept the premises and definitions of something like "basic math" then 2+2= fucking FOUR because THATS WHAT WORDS MEAN YOU FUCK. Or we can accept some other rules and then 2+2=whatever. The point is TELL ME THE FUCKING RULES AND THEN WE BOTH FOLLOW THEM.
CHOICE B - Argle-bargle glyph-glop, floop promble fpppht grook. *Grunts and bangs rocks together*
That's it. There's your choices. Either words mean things, or whaaaarhgharbl.