The joke at the time was that if your machine was more than 6 months old it was obsolete. So many aspects of computers were developing at a breakneck pace it was almost impossible to keep up.

The Bates 4000

https://www.youtube.com/watch?v=_2yjjHzifL8

Yeah, I had a pretty new PC (my first one after heavy-heartedly switching from the beloved Amiga to the despised PC) when Doom was released, and all my friends would come over to play because it could run it full screen (older 386 and weaker 486 CPUs were not fast enough, so you had to reduce the size of the game screen and play with an ugly static border around it). Then just a few years later I installed the Quake demo and all I got to see was an error message. The PC had a pretty exotic IBM "Blue Lightning" CPU which was a "486SX3", i.e. it ran at 75 MHz internally, 25 MHz externally, and didn't have a built-in FPU - which was a requirement for Quake. So I realized it was time to upgrade to a Pentium CPU...

You say you've had your desktop for over a week? Throw that junk away, man, it's an antique.

We went from Wolf3D to Quake 3 in 7 years.

So from software Ray Casting to full 3D acceleration in that time period.

7 years ago from now we had Uncharted 4, it is behind were we are now but not as much as you would think.

And in some cases games have gone backwards, this video comparing Arkham Knight to Gotham Knights being a prime example:

https://m.youtube.com/watch?v=2L3hVUPSDGc

For comparison, a little over a month from now will be GTA 5's 10 year anniversary, and GTA 6 is still nonexistent. Who thinks the technology leap between 5 and 6 will be anything remotely like the difference between Wolf3D and Quake 3?

But also, only a few years after Wolf3D we got Toy Story in 1995, the first major CGI full feature film. Six years later in 2001 we got The Spirits Within, the first attempted full-feature photorealistic film (it hasn't aged well and it bankrupted the company at a cost of $137 million at the time). And now we live in an age where realtime graphics look better than pre-rendered CGI films from 20 years ago... which also includes Lord of the Rings come to think of it.

And somehow they managed this incredible pace of software development without modern tools like git, or probably any kind of revision control system even (RCS/CVS/ClearCase were available on Unix systems, but in the DOS world I don't think there was anything).

Fun fact, Doom was actually developed on a NeXTStation, so with a Unix based OS (and predecessor to modern day macOS).

>> And somehow they managed this incredible pace of software development without modern tools like git, or probably any kind of revision control system even...

It's not that hard when one guy is writing the rendering code, another doing game logic, one doing artwork, one level design, and one doing sound. Nobody is really stepping on anyone's toes.

Yes, that keeps people from stepping on each others' toes, but revision control systems are really useful even for a single developer working alone, just to track changes, make changes to try something out and be able to revert easily, etc. You can do all that of course by making a bunch of ".bak files by hand, but a modern revision control system makes it much easier.