At current capacity, Bitcoin can't stay at that rate of growth if we want to accommodate more transactions. I'm not too sure about the rate of growth for HDDs, price might have gotten cheaper but the growth of Bitcoin could be faster than the growth of HDD capacity. I have doubts that most people can have enough space for a full node ontop of their own files and would probably just to forego that completely. Coupled with a fairly long initial synchronization as well as a catchup after not opening it for a while.
I have multiple discs and I am not even near the full capacity and having one dedicated drive or partition just for Bitcoin blockchain is not that hard for anyone today.
Let me give you few examples, I think anyone can afford to purchase 4TB (or less) Toshiba or Seagate HDD for under $100 or even cheaper with some deal.
If we want to choose faster Samsung SSD with 2TB we can find them for $250 or cheaper.
Now we can't exactly predict size of Bitcoin blockchain but looking at this Statista chart, I think we are not going to reach even 400GB or 500GB in next few years, and data from Ycharts is showing 142.6% Average Growth Rate.
