It appears that after installing MediaWiki 1.32.2 from the repositories, I cannot finish the configuration.
While the normal configuration steps work as expected, once I get the LocalSettings.php file and I copied it to the proper place, it is not recognized.
So far, I double-checked permissions and checked the content of PHP files leading to the message, but could not find anything which was wrong.
As a MediaWiki veteran, I am surprised about this particular installation problem and there is nothing I could find on the topic.
I also contacted Wikimedia Foundation support, but they pointed out that since it was installed from an RPM source, they would not know if some changes had been done to the packages/files.