At some point, no matter how cheap cold storage is, the "dead" content costs will trump the live content streaming. Like postpone but... at some point content needs to be pruned. What's the value in keeping everything forever? 1 year after the video was last viewed? 5? Like when can you safely purge videos?
It's not just a postponement, old content takes less $ to store over time as well as takes up less % of storage over time. Just because it grows in absolute quantity doesn't mean it will inevitably become the largest costs.
Now if 15 years from now storage has stopped becoming cheaper, the rate of new content has stopped growing, the size of new content has stopped growing, and the old content is starting to become a significant fraction of the operating costs then sure. At the moment (and for the last 15 years) none of those things is happening though.
At some point, no matter how cheap cold storage is, the "dead" content costs will trump the live content streaming. Like postpone but... at some point content needs to be pruned. What's the value in keeping everything forever? 1 year after the video was last viewed? 5? Like when can you safely purge videos?