Bitcoin's requirement for accurate time is *extremely* loose. A sundial and an almanac is pretty much sufficient.
People talk as if blockchains can function as trustless clocks, but this is simply not the case.
It's likely that the person you're quoting is confusing multiple different uses of the word 'clock'.
Bitcoin only has a timestamp in it at all to keep the inflation schedule on track and make the infrequently used time-relative locktimes work. If we didn't care about those features it could just exclude the timestamp entirely-- and it would still be a clock, one that just ticks in the form of blocks.