This is my current understanding. I am not in the vape industry and i have not vaped for a while; this knowledge may be outdated or incorrect in the details of the PMTA process particularly.

Alright, so first there were indie juice producers and vape boutiques. Nicotine and the liquid (some kind of glycerol, i don't remember off the top of my head) are quite cheap, so early on the money was made off unique flavors. Boutiques would sell hundreds of flavors at cheap places; regulation still looks good because you have no idea what you're vaping.

Then phillip morris companies began selling vape kits at very expensive prices (for both their shitty electronic vapes and batteries and their juices). These are typically lines of 3-9 flavors in around 3 different nicotine levels, and frankly they're all pretty terrible.

However, the major difference between the vape boutique and the gas station are three things:

1. Nobody at a gas station can help you vape the juice at a safe, sub combustion voltage. This is really key.

2. There's no variety of flavors, and they all suck, and the ecigarettes you can buy there are generally pieces of shit desiged to break. Some i've tried are configured at high voltages, leading to an acrid taste and a hugely increased risk of inhaling carcinogens. Bluntly put, a great way to convince smokers not to switch to vaping.

3. The boutiques source from indie vape juice makers. These people are often just a few people and the brands are often in flux.

Now, for the most part i'm for regulation, and there are certainly questionable juices you can get. Off the top of my head, some of the flavorings combust at lower temperatures and are a genuine health concern; i've had my glass tubing cracked when trying out a new flavor. Scared the bejeezus out of me.

However, the way the PMTA regulations are structured, you need to go through a roughly $300k, 500 hour process for each SKU you sell containing a liquid intended for consumption in an ecigarette. Now you need to assign different skus to every (brand, flavoring, flavor version, nictone level) liquid. So this means the indie juice makers, which might have 20 flavors at 6 nicotine levels each, would have to pay $186M to continue their product line. Accordingly, the market no longer optimizes for convenience and sells a lot of nicotine separately to combine at home with the one or two levels of nicotine they already have in their flavors.

However, if you squint, you can see this is optimized for selling a shitty vaping product at gas stations with the money enriching tobacco companies. This is certainly going to put out of business pretty much every vape store i've talked to; the only ones that can survive need a massive amount of cash to pivot into a new product line (or recover from a suddenly absent supply list). If you look specifically at the laws just passed in California, this becomes more clear (not sure when these laws take effect, or if they already have):

1. Vape stores can't help you with hardware at all anymore. They literally can't show you how to change the battery on your own pen.

2. At vape stores, there is a flat $2 tax on every. Single. Item.

I'm probably missing more details, especially on the california side of things. There are also probably some companies that will survive serving this market who aren't Phillip Morris, but i can't feel optimistic about their lobbying power. Finally, i just want to point out that people want to regulate the juices—and i certainly believe it's necessary for the industry to grow—but this style of "brute forcing" every SKU for such a huge cost of time and money seems like beureacracy at its worst, and it only hurts the consumer and small business owner. Furthermore the recent studies put out about "DNA damage" seem to cherry pick the worst possible result to support the conclusion that "vaping is just as bad as cigarettes" without, you know, actually comparing the health effects emperically on humans. I have no doubt vaping is harmful; i have every doubt it's anywhere near as harmful as cigarette smoke.