I also did some digging... Even though malware attacks are on the move there is no need for virus software..
As I said viruses multiply and spread... Malware just reports.. Ergo.. The file system is the target for viruses.. Malware and adware ( except some) are harmless.. Trojans are malware, but they spread...
Daft! But once upon a time viruses were made to "just disable" your PC as no one was interconnected.. Now it seems data is the most required commodity so disabling is pointless... I think Linux and macOS are harder to extract data from so people target the "easy" route namely windows..