John
Why would there be a problem with the way its always been? Where is the oversampling meaningful, in what pert of the spectrum? I am a bit doubtful as to its necessity.
It shouldn't be necessary for properly designed plugins, but many aren't. Basically anything that messes with dynamics (including EQs) need to be oversampled. By the very nature of the processing, new high frequency harmonics will be introduced. In a band limited system, which digital sampling of course is, that will then alias back down to lower frequency content. Only way around that is to oversample, and filter, which is the right way to do it.
Now as to if this will matter, well depends on the content, the plugin used, and the magnitude of the change. It certainly can. There are plenty of cases where you can toggle oversampling and easily hear a difference.
This basically just lets you force that using the host for plugins that won't do it.