I did some clicking, and for about 60 years there's been a "falling number test" (FN) to determine how much of a load of grain has sprouted. This is extensively covered; your Google search term would be "wheat sprout damage," without the quote marks. The lower the FN, the lower the quality of the flour and what it goes into. I assume that the purveyors of sprouted wheat bread have found ways of dealing with it, but one thing's clear: If you buy a sack of flour at the store for use in baking cakes, bread, cookies, etc., you want a high FN.

Low FN wheat goes for a steep discount at the elevator, and sometimes they won't take it at any price depending on the demand. The main use is for cattle feed. It can also be used as seed, but care must be taken because it might not germinate. And yes, it has less starch. Not a whole lot less, but flour made from low FN wheat is not kind to baked goods. I am new here so I cannot post links yet, which is frustrating. All I can say is that the USDA has documented it backwards and forwards, and I found a very good USDA explanation that goes through it chapter and verse.

"Sprouted wheat" varies by the degree of sprouting. (There are plenty of pictures out there.) I didn't look for FN comparisons from the makers of sprouted wheat bread, and I'd be somewhat surprised if any of them would go into that level of detail. My guess is that the sprouted wheat in sprouted wheat bread isn't very sprouted. Or it's combined with non-sprouted. If I'm Mr. Sprouted Wheat Bread Guy, selling a 20-ounce loaf for $6.30 rather than $2.80 for a 24-ounce loaf of regular whole wheat bread (those were the shelf prices this week at my local store), I'm going to use the highest FN possible.

I don't even know if there's a USDA or FDA standard that specifies how sprouted the wheat has to be in "sprouted wheat bread." I say that because, when you do the research, sprouted wheat is framed in negative terms. Something to be avoided, not sought after. Not only that, but as FN goes lower, the dough is harder to work with. I, the theoretical Mr. Sprouted Wheat Bread Guy, would have every good reason to want my flour made from barely sprouted grain. Or, heaven forbid (!!) to simply lie about it. One thing we can be sure of: None of those health food sites (or Harvard) that promote the stuff will do the deep dive. As for sprouted wheat bread tasting better, well, there's always the secret known to every restaurant that didn't go out of business. If I say the word I might be killed, but I will spell it: S-A-L-T.