Hey now! The C64 might have been technically better with sprites, etc, but the Spectrum was way more quirky and British.

Something about the scrappy underdog making awesome games despite the attribute clash, and having the terrible keyboard really set the vibe. Plus the Z80 processor was way more interesting than the 6502, and really set the speccy-folks up for the move to intel in later years.

Back in the day I don't think many would have switched from the Spectrum to the Commodore.