The spirit of your point is right, but: game patches existed back then. The first patch for Half Life was 1.0.0.8 released in 1999 (release version was 1.0.0.5). I cannot find the patch notes or exact release date as my search results are flooded with “25th anniversary patch” results.
What was true is that players patching their games was not a matter of course for many years. It was a pain in the ass. The game didn’t update itself. You didn’t have a launcher to update your game for you. No. Instead, you had to go to the game’s website and download the patch executable yourself. But it wasn’t just a simple “Game 1.1 update.exe” patch. That’d be too easy. It was a patch from 1.0.9 to 1.1, and if you were on 1.0.5.3 you had to get the patch for 1.0.5.3 to 1.0.6.2, then a patch from that to 1.0.8 then a patch from that to 1.0.9. Then you had to run all of those in sequence. This is a huge, huge part of why people eventually started to fall in love with Steam back in the day. Patches were easy and “just worked” — it was amazing compared to what came before.
The end result being that patches existed but the game that people remember (and played) was by and large defined by what it was on release. Also console games weren’t patched, although newer printings of a game would see updates. Ocarina of Time’s 1.0 release was exclusive to Japan; the North American release was 1.1 for the first batch of sales. After the initial batch was sold out the release was replaced by 1.2. That was common back then. As far as I know there was no way for consumers to get theirs updated, or to even find out about the updates. But they did exist.
I’d agree, though I wonder how much of this is how appealing consumers find the competition? None of them seem to be making major inroads at the moment. The biggest competition is also raising prices, nullifying the competitive penalty Netflix would face from that move.