As someone who started using Linux in 1996 (Slackware, of course), I learnt the hard way about compiling packages. I remember trying to compile the kernel, and doing "make config" and following hundreds of options, and not knowing that I then needed to do "make" or "make zimage" or "make install" after any of the config stuff. Obvious, dumb, rookie errors, but still understandable for a teenager coming from Windows. Doing LFS really taught me a lot about dependencies and complexity, as well as understanding of the actual boot process. All of this helped me greatly in later years.

Your experience sounds exactly like mine. I downloaded Linux 2.6 which took 2 days to compile. Then when I installed it on my Slackware system completely hosed it. But learned so much…

I started with Slackware 1.0 on i386.

I certainly do not miss compiling X11!

>Learning how to compile packages manually it was a common skill long before Linux came to be

Right. I used to compile many open source packages from source on many flavors of Unix back in the day, for years. Perl, Python, MySQL, many others. Miscellaneous utilities. Esoteric languages. Even Oracle, once, on a Unix server, right at a large manufacturing company site. Even building Unix kernels from source was common on some Unix versions. And not just for a regular install. Many times, (re)building Unix kernels from source, was the only way to get some software packages or hardware devices or peripherals, like printers or terminal controllers or even hard disk controllers, to work on the system. Typically you would edit some config files or settings files manually, change values of params, or in some cases use a TUI to do that, and then rebuild via a makefile. You had to save the old kernel in case the new one didn't work, and if so, lather, rinse, repeat, till everything did work.

And that practice was nothing special. A lot if people did it routinely. Most, in fact, I'd say. Talking about devs and sysadmins here, not end users, although some of the latter probably did it too.

Many apps, tools and utilities came as source code, often in a .tar or .tar.gz file. You would untar or gunzip it into a new directory, and do your stuff, running makefiles, other shell commands, setting env. vars., etc.