[EvanWard97]

20x more compute isn't much in terms of cryptographic security concerns, no? Ah but triple-DES was recently depreciated.

Definitely sounds right that we'd get an earlier, heavier emphasis on parallelism and hardware acceleration. I'm guessing the slower speed of causality also applies to propagation delay and memory latencies, so there wouldn't be new motivation for particular architectural decisions beyond "God please make this fast enough for our real-time control systems or human interaction needs".

If we got deep learning years or decades earlier, that also seems scary for AI existential risk, as we are just barely starting to figure out how the big inscrutable matrices work, and that's with the benefit of more time people have had to sound the alarm bells and attract talent and funding for AI interpretability research.