Most of the newer channels are taking advantage of the hardware/software advantages that are not available on first generation hardware (some are only available on Roku 3 even, like YouTube) due to hardware limitations. It's not Roku is denying you access, it's that the hardware is just too old to support the new Channels. So, you got a 2050X a year ago (it was released in 2010)? The second generation Roku devices were released two years ago (2011), so you much have gotten a cheap model of eBay or a refurb. You made the choice to get the older hardware at purchase time.
Also, Roku like any other device has improved hardware over time (and keep it affordable for the consumer), which allows channel developers to add features, which in turn could not work on older hardware. It's just the nature of technology, same thing has happened to all the iPhones, iPads, etc. Should I complain that the new Android versions won't work on my old Galaxy Nexus? I am happy I got up to 4.2 (originally came with 4.0).
Roku has made it "right" by having very cheap devices in the first place. $50 or $60 is not a lot of money to replace a nearly 4 year old device.
Roku 3, 42" LCD, Ethernet (6.2)
Roku Stick HDMI, 32" LCD, WiFi (6.2)
Roku2 XS, 25" CRT, Ethernet (6.2)
Router - ASUS AC68U
ISP - TWC - 50 Mbps/5 Mbps