Happy to say there is a fix for this. Essentially all CRMs are susceptible to this spam blocking and blacklisting which is why it's best to set the send and receive options for your mail to go through a true email provider. The reason for this configuration is that these mega-email providers are whitelisted across the internet and cannot be blocked. When/if there is a block imposed on a sender it will only impact the single user sending and not the entire platform.
It's not hard to do, you essentially switch the mail from being sent and received by the CRM provider and use the gateway of the email provider, in our case Office365, but many other services can do the same like Google and others. If you need help configuring this we can certainly do it if you're using us for email.
Finally, we'll post an article for public viewing later today on how to configure this for those that are technically minded and don't need our hands on help to get this done.
Edited by @Alex Snyder to remove the sales pitch in accordance with DealerRefresh rules.