We'd still have to have time zones (except maybe it be more sensible to call them something else), and we'd still have to deal with the amount of daylight exhibiting significant seasonal variations at places that aren't close to the equator.
The fact that we live on an approximately spherical world whose rotation is not tidal locked to the star it orbits, that world rotates on an axis that is not perpendicular to its orbital plane around said star, we have a biology that uses local sunrise to synchronize its internal clocks to the planet's rotation, and we have spread to occupy regions of the world that are not near its equator imposes a lower limit on the complexity of our timekeeping.
We'd still have to have time zones (except maybe it be more sensible to call them something else), and we'd still have to deal with the amount of daylight exhibiting significant seasonal variations at places that aren't close to the equator.
The fact that we live on an approximately spherical world whose rotation is not tidal locked to the star it orbits, that world rotates on an axis that is not perpendicular to its orbital plane around said star, we have a biology that uses local sunrise to synchronize its internal clocks to the planet's rotation, and we have spread to occupy regions of the world that are not near its equator imposes a lower limit on the complexity of our timekeeping.