Well such configuration changes like "apc.enable_cli="1 should maybe be highlighted in the documentation. But in this specific case I think that this parameter was already present in the documentation, but only on day X with a certain update really led to the fact that the cronjobs no longer functioned.
Anyways… The main challenge with your suggestion is, that you can install Nextcloud in about 1000 ways. With or without memcache, with APCu or another memcache. With Apache, With NGINX, with other webservers, which can be configured differently, with different PHP versions, on different Linux distros with different versions of the required components etc… How do decide what to highlight? Mabe they could maintain a changelog for the most common configurations, but even that won’t catch all problems because as I already said. There is not the one right way to install Nextcloud. And many people copy & paste from random tutorials without knowing what they are doing.
As an inexperienced (home) user, you have basically two options:
Use an appliance like Nexctcloud Pi or the Snap Package
Use the manual installation methods described in the documentation (example installation on Ubuntu or CentOS) and then check the documentation for changes, before you upgrade anything on your instance.
To maintain a manual installation, you have to aquire at least basic knowlege about the components involved, so that you can help yourself to some extent. Most things are documented on docs.nextcloud.com, but still require some basic knowledge about Linux, web servers, PHP etc… In addition to that, you should keep your own documentation and document every change you made on your instance.
If you use Nextcloud productively in a company, there is really no excuse if a change like this causeses downtime. In commercial environments, you absolutely have to test upgrades before rolling them out to production. Anything else is unprofessional and as an admin, you can’t blame anyone but yourself, if you didn’t test.
And one more thing…
You don’t always have to upgrade to the latest Netxloud major version, PHP version, MariaDB version, OS version etc… on day 1. The last two or three Nextcloud major versions still receive security fixes. Ubuntu 18.04 is still supported for two years, MariaDB versions are supported for 5 years. No need to imdiately upgrade, just because some commponent has a new version number.
My production instance is still running PHP 7.4 on Ubuntu 18.04 with MariaDB 10.3. I will probably upgrade to PHP 8 and MariaDB 10.6 with Nextcloud 23 , meaning all these PHP 8.0 and MariaDB issues, that are discussed all over the forums, will never have affected my instance. By the time I will migrate, everything is well documented and tested. And still, I will run at least the database migration on a test instance first.