It was the year, your original interpretation was correct. Key thing to notice: The question is asking about a hypothetical situation in which we magically get lots more compute 5 years before 2020, and then asks what happens by end of 2020 in that hypothetical.
Very minor thing but I was confused for a while when you say end of 2020, I thought of it as the year instead of the decade (2020s).
It was the year, your original interpretation was correct. Key thing to notice: The question is asking about a hypothetical situation in which we magically get lots more compute 5 years before 2020, and then asks what happens by end of 2020 in that hypothetical.
Ah that’s clear, thanks! I must’ve overlooked the “In 2016” right at the top of the post.