which was kind of my point, we've seen this happen before. A bunch of people get into the brewery business because it seems like an "easy" and "fun" way to make money, what with all the small breweries getting bought out by the big ones. So you get a lot of people going into the business, then selling out the first chance they get without any real concern about if they're making good beer or not. Then, once the craft breweries get bought out, BMC reduces the quality of ingredients to save money and the people working their no longer have passion for the job. Wash, rinse and repeat until the whole industry crashes on a flood of bad beer.
I doubt that will be the downfall of craft beer. If you built a brand but made bad beer you would fail and wouldn't get bought by a BMC. I also doubt you can make good beer, build a good brand, and have no passion for the craft and only do it for the money (seeing as you barely have to search google to hear from everyone brewing won't make you money for at least 5-10 years). Someone that half hearted without a passion for good beer, and the business plan of "I want to make a lot of money" would never get a business loan to build a brewery.
If they had a lot of passion for the craft and built a good brand and made good beer, then 10 years in got the offer to retire early or they were just tired and needed a break, who can honestly blame them for taking a pay out?
There's so much that hasn't happened yet.
Have they fired all the original staff?
Do the original owners still have general control of the brewery?
Does the beer taste the same?
Are they moving the brewery to another state/location?
You're insane if you're going to judge the already without knowing the answers above. If New Glarus was bought tomorrow I would continue to buy all of their beer happily, until the taste changes, if they fire any of the original staff, or the owners no longer have general control of the brewery.
Leinenkugel's is a good example in my area and I'm less than 20 minutes from the brewery. Now you can argue about the quality of their beers but their standard normal beers are definitely decent. As far as I can tell the flavor hasn't changed, they didn't fire anyone, if anything they expanded a little, and haven't moved the brewery. They're great for the local economy and when I feel like a tasty almost-beer I reach for a Leinenkugels.
Edit: Do not confuse this with defending BMC. I dislike their beer and I'll skip drinking beer sometimes if that's the only thing to drink. But I am a strong believer in "if it tastes good eat it" and by extension "if it tastes good and gets your drunk, drink it".