A C-64 was my second computer. The first one, which didn't last too much, was a Timex-Sinclair 1000 (a clone of Sinclair ZX81). The Commodore gave a lasting impact for various reasons. It had color, graphics at good resolutions, fantastic sound, a decent keyboard and a good form factor, great peripherals, and excellent expandability. Moreover, the games were incredible.

The peripherals were also noteworthy in the sense that you could have similar, "serious" peripherals such as good dot-matrix printers or floppy drives, than your father's "serious" CP/M or MS-DOS business computers; quite a difference from other home computers' idea of peripherals which were substandard or crippled equipment. That is, from peripherals alone, you could make a case of using C-64 even in serious business cases. And I know, I saw various cases where it was used with vertical or custom-made software packages in my country.

For hackers, the architecture was well understood, the memory map open and re-programmable, and the assembly was 6502 (I know the CPU was the slightly different 6510 but the opcodes were basically the same), which was fairly approachable for assembly programming.

You could get some or all of that, but, as the ad referenced by the TFA, you had to pay a lot more dollars for that.