I've used the built-in apps at a friend's house, and they were awful compared to the Apple TV versions. Everything was sluggish, like it was running on something without enough RAM and swapping out to an SD card. If I hadn't used anything else but that, or maybe the Dish Network DVR we had years ago, I'd probably think it's just fine. However, I have used something else, and it made the TV's own apps feel unbearable.
Imagine you're using a brand new maxed-out MacBook Pro, and someone hands you a 2013 HP laptop. The HP is... fine. It displays web pages, lets you load a word processor, and otherwise looks and acts like a laptop. If you hadn't ever used another computer, you probably wouldn't think anything of it.
BTW, I bet a Fire TV or various other options would be fine, too. I just don't have the personal experience to vouch for those. I'm not using this anecdote to shill Apple TV specifically, just to say that there are much better options than the built-in apps.
Imagine you're using a brand new maxed-out MacBook Pro, and someone hands you a 2013 HP laptop. The HP is... fine. It displays web pages, lets you load a word processor, and otherwise looks and acts like a laptop. If you hadn't ever used another computer, you probably wouldn't think anything of it.
BTW, I bet a Fire TV or various other options would be fine, too. I just don't have the personal experience to vouch for those. I'm not using this anecdote to shill Apple TV specifically, just to say that there are much better options than the built-in apps.