> tainted my view of software development as full of lazy programmers not bothering to optimize code

I have the opposite memory of the C64 demo coders, they were masters at optimizing and pushing hardware well beyond what anyone thought it could do. Generally though they would be very focussed on writing a great demo, but they couldn't/wouldn't spend the time putting together a full game - the flashy demo was their goal.

I was a Spectrum games programmer and yes we were pushing the hardware but what I was seeing from the C64 demo scene was on a different level. There were a lot of demo writers pushing the known boundaries with things like multi layer bas-relief scrolling and playing with colours & music. I can't remember their being much of a demo scene for the Spectrum at the time here in the UK.