[hansvm]

Any search of the form "what other interesting commands did I need the last time I did <foobar>?" benefits from being able to see the historical context. Or if I know the particular incantation is one I wrote several times and is very similar to some others then it's easy to search the history for the blocks of popular commands. Or whatever. It's your terminal, but given how fuzzy the interconnects in a mind can be it's hard to know what info might be useful down the road.

To your point about computing power, I think it's only now that it's reasonable to not filter the duplicates. If I want to emulate the dedup behavior it's trivial nowadays to blindly read 1M lines of history and dedup on the fly each time. Using downstream tools doing duplicate filtering/transforming work is similarly very very fast. Disk is cheap enough that I really do want to keep every command I ever write in my history. More expensive compute and disk would make me more likely to turn that feature on, not less.