Happy to help you understand:
Like a lot of people, I owned a C64 and not an Amiga, which was very expensive and uncommon in my country.
Agreed the included Basic was horrible, but I also started my programming journey with it. One upside, unlike with current computers, is that the C64 had an "instant on" appliance feel to it -- you plugged it in, and it booted up almost instantly, greeting you with the READY prompt, ready to go at your command. Turning it off was likewise instant.
You could also write assembly with it.
The C64 had a vast library of games, many very good, and the SID music from those games was simply amazing. It still is. I still listen to C64 music from time to time, and I love it.
The demoscene around the C64 was amazing and -- get this -- it still exists!
Finally, though less importantly, the C64 was a massive success and sold lots of units, and helped kickstart an era in computing, so it has great historical importance.
Hopefully this helped you understand the widespread love for the C64.
"Retro" exists independently of "nostalgia:" it's a broad cultural category that encompasses fashion, technology, and new reasons to appreciate old things. I would recommend Commodore-adjacent stuff—VICE, TheC64, Ultimate 64 in a new case, MEGA65, refurbished machines with new accessories and adapters—to people with a variety of interests that have never seen an original Commodore.
That's true of all the 1980s 8-bit home computers. Oric-1, BBC Micro, Enterprise 64, ZX Spectrum, Amstrad CPC, whatever. Turn on; beep or click; ready to go.
But with an Oric or a Spectrum or a CPC or other cheap home micros, you could do sounds and graphics in BASIC. Not on a C64.
> You could also write assembly with it.
Also not really fair or accurate.
All mainstream computers can be programmed in assembly. The C64 did nothing to help. It didn't have a machine-code monitor (like the Sharp MZ-80K did, say). It didn't have inline assembly in the BASIC (like the BBC Micro and Acorn Electron did, say).
Comparing c64 to Amiga isn't fair, the Amiga was a generation later. What the c64 should be compared with is the Atari 8-bit systems (400, 800, 65XE, 130XE), Apple II, Colecovision.
Having the 64k RAM, plus sprites, plus a sound chip that implemented ADSR and different waveforms other than square did introduce a lot of possibilities and excitement in 1982 though, even if you tried your best to use them from the absolutely shitty BASIC and/or had to wait minutes for things to load from disk or cassette.
I would even say that the Amiga, at the time it shipped, was the single largest step-up in capabilities of any widely available computer that's ever occurred. Compared to all the other computers available to consumers at the time, the Amiga's graphics, sound, operating system and processing were best of breed. From today's perspective it's hard to appreciate just how stunning the Amiga was versus status quo. It literally drew crowds of people at local computer stores just to watch someone run through all the demos.
While today's PCs are many orders of magnitude more powerful and capable, I can't recall any single increment over the decades being nearly as significant across so many different dimensions (visuals, sound, speed, OS, UX, I/O, etc).
The Amiga 1000 was a decade ahead of it’s time, but Commodore sat on its ass for longer than that, with very little investment in upgrading the thing.
I say this as someone who went from a c64 in her teens to the Amiga in her twenties, and held on to the Amiga well past the time when it was obviously dead in terms of technological prowess and software availability.
The c64 was also a lot of people’s first taste of programming in a time when C compilers cost hundreds of dollars.
And if you don’t understand c64 nostalgia, I bet you must be even more befuddled by Spectrum nostalgia. Which was even cheaper and shittier than the c64, but completely ruled the UK for a while.
Now, we run npm and have barely any idea of how any of it works. That makes sense in a way, things get bigger and more complex. For me at least, it's not fun in the way coding on a 8 or 16 bit computer is.
Then you compare it to things like the Amiga which was incredibly advanced for it's time with amazing graphics and sound that even today are very playable modern-feeling experiences. For an example of what I'm talking about here's two clips (the whole video is good): https://youtu.be/kjapiUQOi2s?t=834 https://youtu.be/kjapiUQOi2s?t=1502