I agree with the other comment here. But the prices aren't higher because Remarkable or Onyx Boox (or, or...) are "small companies", they're expensive because they want it that way... or do you think that any Chinese factory can't supply the high demand they're having? Especially BOOX which is the most successful Chinese company selling e-ink devices like hot cakes, and pushing 5 new models every 6 months. They know they're a "niche" product and it works for them now, at least until bigger Western companies decide to join the game. Part of Amazon's selling speech right now is: "Weeks of battery life, no distractions from notifications or social media" straight from their Kindle store, and they're giving it (dunno). Besides Amazon has a bigger reputation, excellent costumer service, spare parts are available everywhere (even for their very old Kindles), replacements, occasional deals and a cheaper price tag overall (selling books and customer's personal data is their businesses)

Like you said, BOOX customer service is non existent and they usually blame the user for everything, you'll be practically buying (an expensive) product without any real warranty at all... the average battery lifespan on any Android device is 3-4 years, taking in account that you have to charge your Android e-ink tablet once a day (instead 1 a week with a Kindle) there are more chances of facing problems and ending up with a paperweight (instead of a Paperwhite haha) after a couple of years. While
I know some friends that have been using their Kobos or Kindles for almost a decade. Pure Android takes a big toll on the hardware, yeah you can do more with it, but it's not as reliable and prone to failures too... especially when the apps you're running aren't optimized for THAT device in specific. Imagine if big companies like Samsung face several problems every now and then when making and testing phones... then what a "small company" can do? 

A sidenote: Remarkable, Supernote, BOOX or any E-ink company isn't inventing anything new, all those features are already available through any Android (non e-ink) device or are app specific features... they just implementing them on their e-ink devices or ecosystems... so saying "XXXX did it first then Amazon copied them" is partially incorrect.   

The degree to which amazon is slow rolling, adding features is completely just a way to end up price gouging by the end.

Remarkables are expensive because they don't make very many of them, and it's a tiny company. they have very specific features.The devices are really, really solid. they are absolutely out of their minds with the price of the pen that you can flip over and use, like an eraser, and they're pretty out of their minds with the keyboard price as well. but they don't even make that many of the devices they make even less of these extra peripherals, so it's just a supply thing.

But amazon can add all the features that remarkables currently have immediately.  they're not using mystery technology. but for no reason, they don't, but that way, they can release one every year and go, look, it has this new feature. It's like everybody's had that forever. We just want an american company to have it.Because nobody wants to buy a boox since it's made in china, and if something goes wrong with it, their support just kind of blames you

And I love remarkables, it'll take a lot for me to actually get kindle, and I like the fact that it doesn't go online in a meaningful way because I don't want every single device. I have to be connected to the internet, but sometimes I want a tablet that connects to the internet and if it was an eink tablet, that would be good.