Some is changes in the underlying tech of regulated mods, but much, imo, is just marketing. There was huge product turnover in the run-up to mega watt mods with 18 21650 batteries, but the power wars seem to have slowed down. Similar shake out when TC came on the scene.
Getting hardware that does what you need is the only important part. From then on, anything else only needs those specs to work for you. Higher specs can give you room to experiment, which can be fun.
But it's a growth industry, with many companies competing for our $$, and the thinking seems to be there has to be a new latest and greatest every month, whether or not anything but the case has changed. Of course, the case makes the mod - as far as hand feel and visual appeal are concerned
With claims of new and improved chip sets, they hope to get their share ')
While many of us have been building our vapocalypse stash of hardware and nic, no, I don't think the turn over is due to us or to the current politicaly chaos. The FDA and State and local governments have been chipping away at us for years.