You seem to be confusing Determinism with Fatalism. The determinist view is just that all events are subject to causality, whereas the fatalist view is that all events are subject to some predetermined fate despite causality. In practice, fatalists tend to be more depressed and irritating, while determinists tend to drive around expensive cars and generally be much cooler.

Supposedly it's an urban legend that he even said that, because no one on the internet can actually source the quote. And if the internet can't find it, then it probably doesn't exist. To sate those who want at least something, however, here is a relevant quote from 1989:

"I have to say that in 1981, making those decisions, I felt like I was providing enough freedom for 10 years. That is, a move from 64k to 640k felt like something that would last a great deal of time. Well, it didn't - it took about only 6 years before people started to see that as a real problem."