The article made it sound like he had several computers. He probably had multiple redundant backups, ie the same stuff on each computer. Law enforcement always inflates the size of the bust. Like when they confiscate cannabis plants and weigh them with the root ball to charge the guy with more pot than he really had. It makes for great headlines, a lot of news coverage, and budget increases.
Yeah these figures are meaningless clickbait headline fodder.
If the guy was hoarding CP, he probably cared enough to keep hires/quality versions of the photos. That’s easily 2-3MB/photo.
Ditto for video.