Managing apps on Apple TV devices; Can you bring your own account (Hulu, etc)?

I'm using a 2012 Apple TV device (A1427/1040p), which of course is no longer being updated. So, it doesn't the current streaming apps available out there. Worse, when I tried to sign in to one that I already have an account for, it only wants me to buy it through Apple. This old one also doesn't have two of the other streaming services I just purchased a subscription for, so perhaps I need to buy the latest model, and I'm stuck with Roku or Android TV for now.

SO: Does the current 4k* model of AppleTV allow you to sign into an account for the third party app without going through the iTunes store?

*has a deal if bought by Dec 2nd