It's not whining - Apple has built a business on the promise that they provide better security on their platform. Whether you believe it or not is up to you, but millions of folks who have bought into the Apple ecosystem obviously do. You say "nobody is being forced to do it [sideload]" but that is an extremely naive point of view. By giving that option, Apple not only would weaken security for those who opt to side load, but also for those who don't! Example scenario: parent and child with same Apple ID. Parent doesn't side load anything because he believes it makes hacking their account easier. Child doesn't know better and accidentally side loads a malicious app that then goes about exploiting both her phone and the family's Apple-ID based data.
As Tim Cook said: if you want side-loading, buy an Android device! Don't retroactively try to tell Apple how it should run its business!