At scale, yeah, it's got a lot going on. Especially if you need to ensure a consistent product, there's a lot of testing and measuring that needs to be done. It really isn't all that complex of a process though. It was discovered by accident after all. Basically you take grain, cook it to make the sugars available, let it cool, and add yeast. Then you wait for a few weeks while the yeast digests the sugars to make alcohol (and other stuff, like the vaccine in this case).

Different grains/sugar containing material, other products (like hops), ratios, and yeasts will make different products, but at the end of the day sugar + (the right kind of) yeast without oxygen makes alcohol. It's called beer when that's wheat/barley and hops usually. It's called mead when it's honey, wine when it's grapes, vodka if it's potatoes and distilled, etc. Some governments have more strict laws on what can be called what (Germany's Reinheitsgebot is notable strict).

The process though isn't that complex. Making a specific thing can be though. A chef at a nice restaurant is going to put a lot more effort in to be consistent than you will be cooking at home, but you're both making the same thing. It's the same for beer.