Well the rationalisation that ghouls 'should' be wearing armour, in instances like in Necropolis and Gecko (pressure from the Master's army and Vault City respectively) is why I questioned the reasoning in the first place.
...
Well, I hadn't really been arguing that they
should have been wearing armor in Necropolis and Gecko, only that I didn't see
why they
couldn't have.
Absence of proof not being proof of absence and all that. Simply because Ghouls aren't portrayed as wearing loads of armor in Fallout 1 and 2 doesn't necessarily mean there's any particular canonical evidence that they aren't perfectly capable of doing so. At best, it only proves that the Ghouls you ran into in F1/2 didn't wear armor of any kind. There's no real proof to extrapolate anything beyond that apart from rationalizing each of our own preferences.
Seeing no Ghouls wearing armor in the original games and then concluding that Ghouls
can't utilize armor isn't logically any different than playing a game that takes place in the North Pole where everyone wears Winter Coats and then for the sequel saying there's a flaw in the canon because no one wears cold-weather clothing, even though the second game takes place in the Tropics. If at any point in the original games I had come across a Ghoul saying "Gee, I sure wish I could wear that Leather Armor - too bad I'm a Ghoul..." I wouldn't be having this discussion.
It could be quite uncomfortable for a Ghoul to be running around wearing layers of armor - doesn't necessarily mean that the temporary discomfort might not be worth the added protection at times. It's not like there's any real reason they have to be permanently welded into the armor they decide to wear, or anything like that. And as far as Fallout 3 goes, armored Ghouls are still generally the exception to the rule. It's only the more violent-minded Ghouls you see so-equipped - they could be specifically gearing up for a battle (deciding that a few hours' discomfort is worth the added protection,) or only don such equipment when combat looks likely. It's not specifically shown, but I also never see my PC going to the bathroom, yet it's less of a stretch to assume that's happening at some point than concluding that because my character doesn't urinate he must have been surgically altered to bypass such a need.
Anyway - it's still just a matter of opinion. There's no conclusive evidence either way, between the two game types, on this specific issue. All we know in Fallout 1 and 2 is that Ghouls don't wear armor - there's never any explanation about why that is so. So it's "canon" in the earlier ones - at best - that in those instances where you ran into Ghouls they either had decided not to, or were unable to wear armor. In Fallout 3 their interpretation of the canon is that Ghouls can do so (because there is no canon-specific evidence that says otherwise.) Looking at the spectrum of Ghouls you run into, it's still the exception to the rule, for any number of reasons likewise not explained.
To conclude - I don't see how it's specifically against the Fallout canon to have Ghouls wearing armor. Just because they didn't appear to in the original games doesn't logically point to any evidence that they were unable to.