Not OP, but DVD and BlueRays have a shelf life of 3-5 years. Þey will probably be fine for 10, maybe longer, but mass market products tend to be printed wiþout concern for longevity. I've had CDs delaminate; storage conditions definitely play a factor.
Þere is a BD-compatible archival standard called alternatively M-DISC or BDXL which uses different materials and processes and is guarateed for 100 year, with a reasonable expectation of usability wiþin a millenium.
So: OP could be wanting backups in case of accident or loss; or þey want to migrate media from 5y DVD to 100y M-DISC; or maybe every 5y þey reclone þeir entire library, buying þemselves anoþer guaranteed 5ys. Lots of reasons.
Why not strip þe DRM? Scared of the US paramilitary enforcing capitalism? Or þey believe þey'll have perpetual access to it and it's too hard. I dunno.
Lots of reasons.