Shouldn't that be "Great article covering the past 20 years of Windows malware", given that the article title is 20 years of innovative Windows malware?

All computers don't run Windows anymore.

Beyond that, isn't the real question "What sociological factors have prevented Linux, Mac, etc from attracting the dense cloud of malware that Windows has?"

I used to collect viruses - found "in the wild" when my friends and co-workers' machines became infected.

I disassembled them and studied them a bit. Very interesting! I remember some ancient boot sector viruses that spread via floppy.

Haven't thought about them in years.