That could be mostly true of some things like the starches, but with the caveat that the industrial processes used today aren't always the same as what was done traditionally or what I might do in my kitchen, and often involve new/synthetic/potentially toxic compounds.

Pea starch might be the most benign of all of these. I'm not making an argument that pea starch is bad either, just that it's not quite the same as peas, and isn't quite the same as home-made pea starch, and we don't really know if this is a problem.

For example, with pea starch, they use defoaming agents like siloxanes, as well as sulfur dioxide, sodium hydroxide, and others. And, because it's a concentrate of just part of the plant, you might get a heavier dose of pesticides or heavy metals depending on what part of the plant these bind with. (Sure, if you eat equal portions of each part of the plant, extracted, this factor would balance out.)

There's a spectrum of course with these things. Some things like refined oils might be far more harmful than the extracted starches based on the chemistry I've looked into. I'm not particularly afraid of pea starch but I just don't buy or eat processed food generally unless I'm in a pinch.