If they had been designed to be, I think they can. In the case of the Commodore 64, which turns 40 this year, there are many that run fine today, but some earl

If they had been designed to be, I think they can. In the case of the Commodore 64, which turns 40 this year, there are many that run fine today, but some early revisions have chips that were always prone to run hot. Also, the I/O chips could get damaged from using faulty or alien peripherals because the ports hadn't been designed to protect against them. My 30-year old Amiga 1200 had to get new capacitors last year but my five year older Amiga 500 didn't — because it had capacitors of higher quality in the first place. An important aspect for longevity is also to design to make parts replaceable: for repair or upgrade. Some people do use 40-50 year old IBM Beam-spring keyboards with their modern computers, but with a new circuit board that has a USB controller.