I don't think that's all that strong. It's reasonably well-known that processes such as heating, drying, canning, and so on tend to reduce the nutritional value of fruits and vegetables - such as vitamin B and C, sulfurophane in broccoli, antioxidants in blueberries, etc. A quick google should reveal a ton of studies. So it might not be surprising that extracts have these kinds of issues as well.
I think OP is probably right that these meat substitutes are less healthy than eating veg in its raw form, but perhaps the question should be how they stack up nutritionally against the red meat they're replacing.
Yes, but not all processes destroy nutrients. Frozen vegetables are just as healthy as fresh (possibly more so). And it appears whey protein (in essence, protein extracted from dairy sources) is very healthy; again arguably healthier than an equivalent amount of protein obtained directly from "raw" dairy sources (cheese, milk, etc.).
Obviously pea protein will be missing out on some nutrients found in the parts of the pea which were discarded, so may not be as healthy as raw peas, but I understood OP to be saying that pea protein may be actively unhealthy, and indeed, that anything but unprocessed "whole" vegetables is unhealthy. That's seems unsupported by current science.
> pea extracts like protein powder and pea-based fake meats are likely not
>> That's an awfully strong statement. Do you have any evidence or cite?
It depends. Peas belong to the Fabaceae family or Leguminosae that is a big family of creatures expert in alkaloid's design.
Sweet Peas are in the genus Pisum, that is closely related with the wild peas Lathyrus. Lathyrism is a well known neurological disease. Is a permanent damage triggered by eating too many peas from Lathyrus and related genuses. For survivalism and foraging purposes, wild peas must be put in the "not edible thing unless really fainting" category. And only in small quantitites. Not even cooked.
Thus, flour of raw peas should be a little poisonous also until cooked. Workers should have been provided with accurate protection against breathing accidentally the raw stuff day after day (and should assure to wear it). Neurological damages are permanent and not funny.
By the same reason, even if seems convenient and fast to just make a smoothie with raw pea flour you must assure to cook it before to eat it (OR that was yet cooken by the maker before to sell it).
That's an awfully strong statement. Do you have any evidence or cite?