I think it's good to have 4K these days. You get more flexibility in editing the footage and 4K is pretty standard now for TVs.
4K is standard for TV hardware, but not necessarily TV content. I think most shows are still in 1080P. Tech-wise, HDR has been a bigger visual difference than 4K. Many people cannot tell the difference between 4K and 1080, and one primary reason for this is that in video there is often motion blur anyways. (The case is different for stills). I might also add, if you really want to create "UHD" content for high-end TVs, you'll need a HDR + 4K workflow, which balloons hardware requirements. Pros will go this length and sell the content to reap profits, but if you're not intending to sell your content like this, then I'd recommend making life easier on yourself and create in 1080p at least until computer hardware catches up.
Why does it matter if there is any TV content in 4K right now. For people creating memories or any other kind of video they value, they can view that on the hardware available right now, in full quality. They can also make sure their video quality is as good as possible far into the future, a future in which 1080p will probably be a good joke.
Lots of devices can record 4K and also play that content back without issues, hardware is only a problem if editing the content, and there is no real need to do that for most users. They can always edit it later as hardware becomes more powerful and widely available.
Why store memories or other valuable work in an inferior format?