As long as you keep a backup of your old app bundles on your computer (for instance using Time Machine) I don't think it's a problem to load old apps. The exception being if some of those apps require online services that are no longer available.
Keeping and installing old copies of app bundles doesn't seem like a very viable option for non-technical users.
Using outdated and unsupported versions of software doesn't seem like a very viable option for non-technical users.
I don't like your comment. You use the same words to directly counter the parent, but these words don't match the case. What do you mean by "viable option" here? Some "options" for non-technical users are in this thread's first comment.
Maybe not, but it is exactly how software has worked since approximately the dawn of time, and it is exactly what the grandparent comment was proposing should be allowed.
Of course the non technical user is not generally the one complaining.