>HDDs are quite fine for data chunks in the megabytes.

Exactly. SSD fanboys show me a similarly priced 30 TB SSD and we can discuss. A bit like internal combustion vs e=car - the new tech is in principle simpler and cheaper, in practice simpler and pricier, with the promise of "one day" - but I suppose LCDs were once in a similar place so it may be a matter of time