I've learned my lesson, though, and now I just pirate Netflix content I want to see on my TV so I can watch it on Kodi. I'm not planning on replacing my TV any time soon and getting Netflix integration into Kodi is too much of a bother. Unless Netflix comes out with an official Kodi addon, I'll just stick to this setup.
Thankfully it's been fixed for many months now.
But yes, the challenge with building the UI for a product like this is that it has to run on everything. Android from 2014? Yep. Some weird vendor Android that was installed on TVs the same year? Yep. Apple TV? Yep. Roku? Yep. Every video game console and some handhelds? Yep. And so on. Your build target list is insane. Luckily for them, they can get access to SDKs or dev kits that Mere Mortals cannot—for instance, IIRC there's a "big-boy shops only" SDK for Roku that lets you link in C/C++ libs and have much lower-level access to drawing routines, since otherwise it'd be impossible to make things like Netflix look as similar on there as it does elsewhere. As a user, I wish they didn't have that access, because it'd perform better if they had to use the same very-efficient UI the small players do (plus it'd make it harder for them to have the damn auto-playing videos everywhere).
These channels to have support for browser, phones, android, and smart TVs. They prolly just ain't trying to make one Interface work for them all.