I’ve found radicale more stable in my implementation, but both are very good and are pretty similar to use.
If you already have NextCloud/OwnCloud it would be a good to use the Calendar that is already built in, but it doesn’t make sense to install those for a calendar when there are better options available.
Cmon bro, just one more datum. That’s all we need. One little piece of data and that’s it. Cmon, please?