My parents have an Android TV, they have to regularly reboot it to fix its (wired) network connection. Nothing else on the network has a problem.

Meanwhile I have a second-hand Apple TV and it's great, but if it weren't great I would keep my television and replace it with a Fire/Roku/Whatever device.

I suppose they could keep their smart TV and hook up a less shitty external device to do the smart things, but then the smart TV is just a dumb TV that takes 5x longer to boot and presumably wastes extra electricity in the process.

If I had any faith in these Android-based televisions to get long term software support and be at all reliable maybe it would be different, but based on track records in the ecosystem I absolutely don't. The life span of a television panel is many times as long as the effective useful period of an android device.

Depends on the implementation. My parents samsung tv has become unbearably slow and a factory reset doesn't fix it. I assume updates are to blame. Others are also reporting that their smart tv started showing adverts after years of owning it.

Since the panel is expensive and the brains are cheap, it makes more sense to have them split.