That's true. When I didn't have internet at home in early 00's I did far more tasks than today.
The thing is today, except for Debian (DVD/BD sets/ISO's), Hyperbola (offline mirroring, the repos are small) and few systems more, working offline seems odd as lots of things depend on fetching software via repos, or documentation, where you can't get that any more for lots of programming languages or software such as MS Office.
But, well, at least systems like 9front have static binaries, so they are easily shareable, and all the documentation it's offline.
And, universally, there's mbsync/msmtp for email, and news spooling via usenet. Sometimes I'd love an NNTP->Usenet bridge, so everything could be done offline from nearly any modern OS since the 90's, and just connect once to answer to all threads.
Turns out there is still a lot of uses a computer can serve without being plugged into the Internet.