It's a choice. PackageKit is going to warn you about new updates and do the updates for you via Discover or Software Updates, but in case of conflict or issues, it'll just throw an error and give up. You'll then need to use zypper. This is why power users tend to advise to always prefer zypper anyway. The risk for them to forget to update is very limited.
If you know you'll think about running zypper from time to time to update and prefer this way of doing things, then disabling PackageKit as the doc you linked suggests is a good idea. Note that e.g. Discover will still be useful to handle Flatpak.

It's not just UI wise.
They explain it on their website : their internal logic for a document is based on OOXML logic, while LO is rather based on a ODT-based logic. So compatibility with Office is more straightforward in OO (though we know Microsoft is not quite exactly following the OOXML norm, so still not perfect...)