I was unaware of that, so thank you for the education. But for what it's worth, I have never seen a Linux system which didn't have user crontabs. So even if not

I was unaware of that, so thank you for the education. But for what it's worth, I have never seen a Linux system which didn't have user crontabs. So even if not universal, it is at least very widespread to the point that you can bet on its presence.