If humans were to colonise Mars, I suspect they might adopt a hybrid calendar, combining the Martian day with the Earth year

I think for humans on Mars, the local day-night cycle would likely be much more important than local seasonal cycles. Plus for a long time they’d be dependent on Earth (financially, politically, etc), and Earth years are a natural unit of Earth-centric planning, plus they’d see themselves as part of Earth-centric human history. And maybe eventually they’ll wean themselves off their dependence on Earth, but that would likely take centuries, by which time such a hybrid calendar may have become deeply embedded in Martian culture, and the use of the Earth year might endure long after the original motivations for it ceased to apply

So I could see our current Earth-centric year numbering system being maintained as humans spread out through our solar system. And if eventually we spread to other star systems, we might take that with us too