Malicious LNK files are easy to block with a spam filtering solution as it is unusual for these files to be sent via email. The SVG image format is more commonly used, so while these files could be blocked by an antispam solution, doing so would likely have an impact on some end users.
Given the change in the file types used to spread malware and ransomware, organizations should take action to prevent infection. End users should be warned about these file types and told to exercise caution. Policies should also be introduced that prohibit the sending of these file types via email. Better still, both file types should be blocked by a spam filter. If they are needed, an alternative method of transferring these files should be used: Google Drive or Dropbox for example.