>>106322158
Buy bigger hard drives. At roughly 50GB each you could fit 240 BD ISOs on a 12TB drive. Reencoding lossy versions should be for portable use, not to supplant your original; that's how you end up with only shitty 64kb/s MP3 rips being the only existing record of rare bitrotted CDs.
I have a bunch of huge VHS and LD captures but I would never permanently delete the original capture files (maybe lossless compression like FLAC or 7zip at best). Likewise with 6K ProRes files of 16mm/35mm film after cleaning up and reencoding them into something presentable, even if some of them take up a whole terabyte per reel.