What will happen....
People's tastes will change and a lot of these companies will be wrecked.
I live in the Hudson Valley - there are hop farms popping up everywhere. My retirement plan is to buy up that real estate when people decide that they no longer want to drink beer that tastes like someone blended a hop plant.
If that never happens, I'll be okay buying up the real estate under the craft distillers and hard cider brewers that are also sprouting up like weeds.
5 - 10 years ago it was all about the Belgians. Some of the best beer bars were Belgian only. See Brick Store in Decatur, GA. Nowadays if you don't have a DIPA on tap you're in trouble. It used to be just Pliny and Hop Slam. Seems like the bourbon or oak or wine barrel everything is becoming a bigger thing. It use to be just KBS and BCBS, now every RIS has a bourbon barrel version. I've even seen oak and wine barrel saisons and sours now. Also, I've noticed slight variations of various beers that never was a thing before. This coffee bean or that coffee bean, or see Ballast Point with how many different types of Sculpin?
You're right though, tastes change, but brewers adapt. Craft brew has been coming and going since they were called microbrews in the 90's. This major craze right now reminds me of Moneymaker and Sammy Farha making Texas Hold'em huge. At that time, if you knew how to play, you could clean up. Nowadays everybody is a poker star. Nowadays everybody is a a master brewer. The fat will be trimmed soon.
One thing for me I've noticed, is the acclaimed beers are outrageously priced now. $25 for a bomber, or $18 for a 4 pack. If you know a local beer is good, you can save a lot of dough. But when there are 100 options, its hard to know whats good except Beer Advocate's top 250.