I don't have any hard evidence but I'm sure you could find some. I certainly don't remember ransomware attacks being very prevalent prior to last decade. They all seem to request cryptocurrencies (I can tell you're a coin head because you refer to them simply as crypto).
Without cryptocurrencies ransomeware would largely go away. Sure there'd still be cybercrime, hacking, data breeches etc...
I remember that Walmart or the govt or both made some change where these didn’t work the same way and lost their shine for ransom payments.
Thin on details but the as I recall the options for paying ransoms easily prior to crypto were tightening up.
That said, I’m 100% against the idea of fighting crypto to solve this problem. The liberty of humanity needs anonymous cash despite the risks that come with it. Better to address these problems on the data security and resiliency front.
Judge me how you will, however, I do think I see your point that crypto might be contributing to this new form of extorsion. I was only trying to get more detail. Which has now been provided.