I paid $300 AUD for the R1 in March of 2015. I paid a further $380 AUD for the XR500 in May of 2018. I'm happy with both purchases. I've replaced routers on roughly a 3 year basis for two decades, so it's nothing new...everything has an expiration date.
The R1 router itself was not impressive - it's a bland, small, beige brick and I would never have bought it for the hardware. I bought it for the software and to support the little guys with the big idea. The time I spent with the R1 for 3 years was worth the money, but the hardware is well and truly out of date and in desperate need of an upgrade.
I've wanted a new router for some time, but stuck with the "little box that could", in part due to brand loyalty and in part due to the promise of DumaOS and a couple of features that could further elevate Netduma's status as the leading gaming router software developer. I don't feel that loyalty has been repaid as DumaOS is still MIA on the R1 with no concrete sign that it will happen any time soon. But life goes on and the butthurt will fade over time.
Although I am disappointed with how DumaOS has been handled on the R1, I'm very happy that Netduma, a software company, has partnered with arguably the best gaming router hardware brand in the Nighthawk. There's no way that a small indie company could develop hardware in-house to compete with any of the big brands, so it makes perfect sense to focus on their core competency and build DumaOS as robustly as possible. Yes, there is better router hardware out there (not by much), but they can't do what DumaOS does at the same price point, so it's a happy medium that Netduma could never have achieved on their own.
Even if DumaOS hits the R1 (I'll assume in a cut-down form), the reality is you're running very basic, old hardware that is missing rudimentary features like 5Ghz wifi, a strong wifi signal, wireless ac, WPS, guest wifi, DMZ, port mapping, content filtering, DDNS, bridging, traffic monitoring, DLNA, basic NAS capabilities...the list goes on and on.
Focusing on software development while hand-balling the ridiculously expensive hardware and marketing side of things to Netgear is a fantastic match for Netduma and I applaud them for the move. I'm sure it was difficult to give up their independence and be perceived as selling out, but we're getting a far better product in return. I'd just like to see a better transition plan for R1 users to the XR500 (and beyond) because you will be left behind, sooner or later with a dated, crappy router chugging along on crippleware.
Long story short - DumaOS might drop on the R1 sooner or later, but my guess is it'll be DumaOS Lite. It won't do anything to address the weak aspects of the hardware, nor basic software features you'll find on every other router. Get over it and upgrade to the XR500. Your pockets will be a little lighter and you can still be pissed about a broken promise, but you'll be happier for it.
Everything you said makes sense except for the last bit about buying the xr500 this is exactly what netduma are wanting you to do. Personally I will never buy or recommend anything linked to netduma again if I buy another router it will probably be the r7800 which is basically the xr500 without Duma OS