I avoid any foods with HFCS as well - but most of the HFCS in foods (not beverages) have the same proportion of glucose/fructose as table sugar - and we split that sugar into glucose/fructose early on in the digestion process - early enough that the fructose goes straight to the liver (small intestine->hepatic vein->liver).

I'd also point out that solid fruit (e.g. an apple) has fructose - but not enough to cause a problem, so long as not processed into something drinkable. I get that the text is more about that, but the picture is someone biting into an apple.

Aand, yeah, if you're on keto, pretty much any quantity of fructose can kick you out - but you probably knew that.