Have you forgotten all the extortion that happens because of all the encrypted files? Just because people kept opening bill.pdf.exe.
A lot of companies don‘t allow their users to download any files from cloud services an quarantine and manually review e-mails with attachments and download links. A lot of companies running Windows are also starting to use AppLocker which is a way to only allow whitelisted executables to run. So yes this is a huge problem and billions of dollars are spent on it (be it losses through attacks or money spent on countermeasures).
A lot of companies don‘t allow their users to download any files from cloud services an quarantine and manually review e-mails with attachments and download links. A lot of companies running Windows are also starting to use AppLocker which is a way to only allow whitelisted executables to run. So yes this is a huge problem and billions of dollars are spent on it (be it losses through attacks or money spent on countermeasures).