Oat milk is just oats blended in water. The research is minimal. The marketing is where they put most of their money.
Most retail nut milk is actually mixed with a variety of gums and other texture enhancers.
Fresh, homemade oat milk is actually really easy to make by that process, but store-bought oat milk needs to have consistent flavor and texture/mouth-feel. So there is a bit more that goes into it.
This is also true of other non-dairy milks. That’s why I only use Trader Joe’s or Westsoy shelf-stable soy milk for making yogurt. No gums.
I think there is a huge difference in the thing you are describing and e.g the oatly barista.
There are a lot of oat milks that taste very different or not at all. To get the right taste and consistency, you need some research.
You’re the only one talking about niche/specialty products though. Not denying that those products require extensive research, but I doubt that those products alone are responsible for the considerable markup on the typical alternative milk products, which truly are closer to “oats blended in water”, and probably make up a majority of sales.
Plus vegans will pay anything in order to imagine themselves as being better than meat eaters.
