NA essentially was the console market back in the late 70s & early 80s, not only being the home of the console market (Atari, Mattel, Coleco, etc., were American companies) but also where nearly all consoles sales originated from. Atari was utterly dominant, with the 2600 capturing the vast majority of all sales. The 2800, the Japanese version of the 2600, wasn't released until several month after the Famicom was released. The Famicom was essentially the beginning of the console market in Japan and dominated the Japanese market until the SNES came out. Of course, Japan was a major player in the arcades, but they were a little late to the console market. As for Europe, the 2600 came out around the same time there as in America, but their console market was always much smaller. The only source I could find on European sales of the 2600 were of course VGC, who claims only 3.35M 2600s sold in Europe, which sounds plausible given how low Nintendo and Sega sales were in the 8-bit & 16-bit eras relative to the NA market. Still, the market pretty much bottomed out in Europe as well.

So, the NES save console gaming in NA and made it relevant in Japan, while Europe is a more ambiguous case. In any case, had the NES failed to revitalize the console market in NA and make consoles relevant in Japan, we might not be playing consoles today. It really was a make-or-break moment for the industry.

You are correct. In other words, gaming was fine in the rest of the world. The correct term would be Nintendo helped console gaming in NA. The only company that affected gaming worldwide is Sony when it debuted the PlayStation, which made gaming mainstream and an entertainment option as valid as movies.

That's what you took away from it? The console market was essentially dead in NA by 1985 and consoles weren't really a thing in Japan until the NES. Europe was essentially an irrelevant market in the 80s. Had the NES not taken off like it did, there likely would have never been a PlayStation. The PlayStation itself began its life as a joint Nintendo-Sony effort to make a CD add-on to the SNES, but the deal fell through and we got the PlayStation as a standalone system. Gaming was already "mainstream" in America and Japan by time the PlayStation debuted anyway. The PS1 barely outsold the NES in the U.S. and Japan, and the overall market in both regions grew by about the same rate as it did in the jump from the 8-bit to the 16-bit eras. The PS1 did popularize consoles in Europe, but again, that was entirely contingent on consoles regaining relevance in America and establishing relevance in Japan, and that was all thanks to Nintendo. The NES did save console gaming.

Now, would video games still exist in some form? Probably, but the market would be vastly different. "Home computers" like the Commodore/Amiga, MSX, and ZX Spectrum would probably retain some kind of relevance, and they would likely still have given way to PCs in the early 90s after Windows 3.0 was released. Whether those would have become as mainstream as consoles is anyone's guess. Arcades would likely have stuck around and may have retained relevance to this day in the West. But without the NES, which had become the face of gaming in America and Japan in the latter half of the 80s, game design itself may have taken an entirely different path. Platformers especially may have never been popular without SMB to revolutionize the genre. Other genre-defining/-redefining/-popularizing games released first on consoles (e.g., Dragon Quest, Final Fantasy, GTA3, Halo) may have never been made.

So, the NES may or may not have saved gaming in general, but it did save console gaming and its success laid the groundwork for everything that followed. Our hobby may still have existed without it in an alternate NES-less timeline, but it would likely seem utterly alien to someone from our timeline.