Nicely put. It's hard to get the orders of magnitude across; that's a good example.
One could argue that the "didn't say 'never'" was implicitly understood. What I don't think most grok is then-incomprehensible scale change; those loading multi-ton 5MB storage units on airplanes couldn't imagine a half-terabyte on your fingernail.
The parent comment above would have been too big to store in main memory for one of these computers.
The comments on this thread wouldn't fit into secondary storage.
It's also useful to remember that was talking about his then present, not forever and ever. He didn't say, "and there never will be."