Just like how Bachmann stuff have an imaginary value...
The value and collectability of an item depends on what people are willing to pay, and how many people are willing to collect it.
Your main point is that technically these items are not HO. You're right, they're not quite HO. But even then, it's like arguing whether a red banana vs a baby banana are actually bananas. It's a technicality.
Perhaps it would be best to look at the overall situation from a real world perspective for a moment to understand better what makes an item "collectable".
True collectability is much more than simply that there is one person, or even a small group, out there that are willing to pay an excessive amount of dollars for an item. In the real world of collecting there needs to be an aspect of quality, or beauty, and true value, as well as a rarity or uniqueness to the item for it to command a
broadly recognized and exceptional value justifiying its collectability and price.
There admittedly are folks today that collect old bottle caps, empty beer cans and so on. Outside of their tiny niche group they are simply looked upon as just more-or-less oddballs collecting old junk, not collectors that are to be taken seriously. The same is largely true of HO Lionel and AF collecting enthusiasts. At best, one can only speculate at their real motivation for "collecting". It may be an attempt to recapture a moment in their long ago youth when they once owned, or longed to own, these low-end and commonly available trains. It's difficult to say, but it is certainly not based on any logical motovation, nor the intrinsic value, rarity, or prototype accuracy of the items collected. The items may be of personal, or perhaps sentimental, value to these small circle of folks, but within the broader hobby they are looked upon as just a bit silly.
Now it can be said that the collecting of say brass locomotives, or perhaps items such as very early Mantua, or Varney, et al., locos could be justifiable as a true collection and the items certainly do have a "collectable" value. The former represent very high quality, expensive, hand-made, miniature replicas. The latter locos would illustrate products of historical significance and perhaps of even greater rarity than brass these days. But common toy trains share no such aspects and are nothing but common toy trains. So...there truly is a distinct difference in recognized collectability in a particular field and simply the acquiring or peddling of older junk, regardless of what the owners may imagine its value is doesn't establish an actual collectability.
I will conclude by saying that I'm not the least adverse to anyone having a "collection" of whatever they please. That's fine. However, by no means does it automatically imply what items one is collecting are actually recognized as "valuable collectables".
NYW&B