Burton has been a consistent advocate for quick entry, but I think it's inaccurate to imply they are the ones driving all the innovation. I rode Switch bindings back before Burton got in the game. I did ride Burton's Step-In bindings (pre StepOn) and those were not great. I haven't ridden StepOn, but they have the same two problems the Switch and SI bindings had: (1) you can't quickly switch over to a board with a regular binding due to the extra hardware on the boot and (2) you need a boot with way more internal structure/weight if you want any kind of boot/binding stiffness. Flow really changed everything by solving these two issues. And as has been said, they also solved it in a way that didn't compromise performance.
Other than Flux (which IMO is good), quick-entry was really stagnant until Burton came out with their new, and much improved, system. It has really started to gain market share over the last 2 to 3 seasons. This more mirrors Tesla pushing other automakers to catch up. I mean, hell, who would have thought Union would collaborate on a binding system with Burton?! That says a lot. I rode Unions before this system and their product, factory and organization seems to be top notch.
I've ridden StepOn for six seasons, but I never saw anyone on them for the first few years, and other than a couple of riding buddies that also switched after seeing my setup and how it functions, people ALWAYS asked me about it. Now, you see them all over the place (and no one asks me anymore, thankfully!). I don't have data on market size, but it's rare to be in a lift line now that I don't see AT LEAST one other person with them out here in Utah.
Also, what you're saying about the boot needing way more internal structure/weight just isn't true with Step On. This isn't a K2 Clicker. IMO, it's a pretty marginal difference, and the Step On Ions fit (and feel) about the same as my standard Ions. Obviously that is subjective and boot fit is incredibly personal.
I do feel that the performance is better than any setup I ran before, but I don't ride much park except for spring laps -- I'm usually out freeriding pow when it's good and carving groomers when it's bad. I like stiff and responsive setups so that's definitely part of it.
I do think FASE will be an option (although not as hands free) that will appeal to a lot of other riders and that's good! I'd like to try Supermatic one day when I get a chance, but haven't yet. I personally think that the landscape will be: StepOn, FASE, Supermatic, and Flow (probably in that order) for a while barring some new advancement that I don't know about. FASE could pass StepOn in adoption if it's cheap, works well and is availabile on a lot of bindings (that people already know and love), but StepOn does have a six year headstart.
I do have to point out that there are always people talking about things they haven't even tried or if so, for only a day. That's nothing new (in snowboarding or anything else), but take everything you read with a grain of salt. There's a lot of opinions (including mine), but at least I am experienced. You just have to trust that I'm an expert rider with hundreds of days on the system...
