We need to also keep in mind that even if only nicotine liquid were banned, since this is the key selling point that leads to vaping in the first place, sales will likely go down considerably over time. Most people who vape for nicotine will have to find other nicotine sources, and they will vape less or quit vaping completely. There will be far less new vapers, as it is no longer an effective substitute for smoking for most people (as most people are at least somewhat physically, not just habitually, addicted). As sales gradually drop over time, we will see less innovation of new products, less variety of products for sale, and fewer shops selling them. If nic liquid were banned completely for a long time, I predict that in as short as 10 years stores will be selling vaping equipment, including no nic liquid, on the side as a novelty product; they will expect few sales, and so they will have little variety in equipment and flavors. In other words, at that point you'll still have to DIY flavors, as fewer and fewer shops will be willing to put work into such a variety when hardly anyone is buying them.
So basically, as an individual, if you're concerned your best bet is to learn DIY, no matter what. If you vape nicotine, stock up if you can afford to - there's plenty of advice around here on where to buy bulk nicotine liquid and how to store it.