I never had a C64, even though it was the 2nd most popular 8 bit micro-computer, during the 1980's, in the UK.
I had the vastly more popular & functionally superior 48 K ZX Spectrum +, Spectrum 128 K, Spectrum +2A and Spectrum +3 (which I eventually ran and IBM 10 M. Byte Hard Drive on).
The spectrum featured the faster & more versatile Z80 processor, 41 K. bytes of user memory (compared to the C64's 38 K. Bytes) plenty o f 3rd party peripherals such as virtual memory pericon modules, parallel floppy disc drives, video capture cards, IO ports, robotics kits, etc.
I've walked around a factory and witnessed a Sinclair Spectrum running a CNC milling machine. NASA even took one (a Timex 2068 version) up on the Space Shuttle, in 1986, to send down 2 metre Ham radio band slow scan TV for schools. The Ham Radio astronaut operator was W5WFL.
All the C64 had going for it was the nicer keyboard.