I feel like period between about 1998-2009 was a sort of "golden age" for video games. I find the history of video games in the earlier days to be highly interesting; how they were technically designed given the more limited hardware, how they were marketed and how the industry developed. But as for as the games that are most fun to PLAY, I find that the late '90s to late '00s has the highest concentration of just outright fun experiences. When this thread was created 17 years ago, we were right in that golden age. Don't get me wrong, I like plenty of games older than 1998 and newer than 2009.

Leading up to about the early 2000s, technological progress made games richer and more fun experiences with each passing generation. The OP touches on a lot of good points showing the evolution of the video game industry up to 2003. Up to that point, each new generation offered something substantially new, something that made games that much better. By the early 2000s, graphics had gotten good enough to where, while not photorealistic, they were good enough to make well-detailed, rich, engaging environments, and the 3D no longer looked muddy and low-detail like it had just a few years earlier. Game budgets were big, but still small enough that even midsize studios got their games on PS2/Xbox/GCN discs; "mainstream" and "indie" weren't quite so separated. It was a creative golden age. Best of all, when you bought a game, it was all there. No patches (except on PC), no online requirements, just a disc, a system, memory cards, and a controller.

What advancements have we really had since about 2007 or so? By the Xbox 360/PS3/Wii era (the tail end of the golden age, in my opinion), we already had graphics and sound that looked pretty damn close to what we have over a decade later in 2020. We've hit a law of diminishing returns on that front. After decades of moving forward, I feel like things really were better for video games in the 2000s than they are today. In the "golden age" online multiplayer was a thing, but it was a facet of gameplay, something extra that could add to the experience of some games. Today it's gone too far, with some games even requiring part of them to be downloaded, even if you have the disk. Many games have been created with the online experience being the ONLY thing considered, completely ignoring the single player experience (the new Battlefront II being an infamous example). There seems to be little creativity in mainstream video games, what with the budgets ballooning from big to ridiculous.
On top of that, mobile gaming. Phones are good for simple experiences like Candy Crush, puzzle/word games, etc. But mobile gaming has killed off handheld consoles (except for the Switch, which is a hybrid), indie gaming studios which ARE producing unique content produce a good chunk on mobile. I'm sorry but I don't want to play long, complex, narrative driven games on a fucking phone with a touch screen.
Not everything about the video game world of 2020 is bad, but it's a definite decline from the past.