I think we may be seeing an organizational issue at work. The job of a design department is to produce design. If there isn't enough new stuff to design, they will redesign old stuff. This serves to advance the critical goal to the design department of justifying their continued existence.

The number of designers who will march up to their VP and boldly declare that all the company's apps are just fine and don't need any kind of redesigning is small.

You get a similar thing any time a development team runs out of feature work or actual stress points in an application they maintain. They wind up reworking the thing mainly to have something to do to justify the continued paychecks until the business thinks of an actual reason.