I think I see where you fit in - deeply embedded systems with real-time constraints tend to use a certified hypervisor solution to separate runtimes. Traditional IT solutions can use Linux KVM or a full Docker implementation. ResinOS fits in the middle.
Familiarity with Docker will allow makers to get multiple runtimes up and running on higher-end (but small) SoCs...but for what type of applications?
There are a lot of companies looking at the intersection of containers and embedded. Some call it "Fog Computing" others "Edge Computing", others still "Industrial Internet" and so forth. We have a number of use cases on the resin.io website of people using this technology in production today, but some of the larger ones we're not allowed to talk about :(. ResinOS does include a full Docker engine however. It's just that a lot more is needed to do containers right on embedded Linux devices.
There's a lot of devices that need to run unsupervised, but still have (relatively) beefy hardware and commodity software. Digital signage stations are one example, some customers want a (relatively modern) Webkit/Blink based browser based system so they can deploy React/Angular/etc based applications on it instead of needing to hire people who know Qt Embedded or similar. The overhead doesn't really matter for such applications: The backlight for a 40+ inches large touchscreen will always consume more power than the other components combined, so you can put in an actively cooled 20W dual/quadcore APU just fine, and having a full OS allows running other services on it (SSH/VPN solutions for remote management, e.g.).
(Disclaimer, we've been doing exactly that since 2011. I've been wanting to move to a containerized approach for years, but our customers are happy enough with the current solution that they don't want to fund it. Alas.)
Familiarity with Docker will allow makers to get multiple runtimes up and running on higher-end (but small) SoCs...but for what type of applications?