So rare to actually have to denormalise for performance today though. Query planners are miles ahead of where they were in the 80s and 90s. SSDs delivered an order of magnitude boost to performance. Rapidly expanding memories hugely increase the how much working set you can hold in memory.

No one seems to talk about this but the "Moore's law has ended" meme does not apply to most database scenarios. Database servers are normally not CPU bound: they are bound by available memory and disk bandwidth and these are both still increasing.