I don't believe this will cause him to go under and I don't 30 people online, some of which don't even live in the area, are gonna effectively boycott the store into oblivion. I am however drawing a comparison to some other examples where multiple online negative reviews caused a store to lose enough traffic where it forces them to close.
Even with 15 or so 1 star reviews left over the last 2 days he still has a 3.8 rating which is alright. However if this had caught on more than it did and he dropped under 2 stars or so, many tech savvy people who check out a shop before going would pass over just from seeing the low rating.
I am more getting at the possibility of something happening, which is possible. I also just wanted to inject some realism into the picture, being that people have families to care for and intentionally either hoping for or trying to destroy someones reputation is over the top.
Shops should be very careful what what they say about guns to the media. That's a known universal fact for FFLs.
Even shops that don't talk to the media, but do stupid moves pay the price. Northshore Firearms is a good example. They had a little event a few years ago and the shop lost a lot of customers over it no doubt.