There are some applications (for example if you're a journalist, documentary film maker, or security guard and need to stream body-cam video to your cell phone), where 1 TB of local storage would be essential.
I don't think documentary film makers or security guards would be typically relying on a cellphone (and the number of them is a very tiny fraction of the phone market)
1 TB will store about 7500 hours of 1080p, that's most of a year, 24 hr a day. Is someone realistically going to store that much LOCALLY where it can be lost stolen or damaged?
It's even ridiculous overkill even for applications like that.
[Professional photographers often carry standalone drives to download their shots, a RAW image from a Nikon can get pretty large, but the sure don't use a cellphone for that]
Are you sure about the estimated number of video hours that a 1 TB disk can hold?
I was thinking that one hour of compressed 1080p video would be about 3 GB for a total of 341 hours.
"Do not seek to follow in the footsteps of the wise. Instead, seek what they sought." - Matsuo Basho