Providers with outgoing spam filters or external smtp can prevent the transmission of malicious email (also known as spam) or files from their networks, thus eliminating the main causes of the inclusion of their IPs in the blacklist.
Hosting providers that use outgoing spam filters or external smtp services to send emails are probably a good option for their needs. Normally, providers use the same server where your website is located to send emails. Normally, this type of provider does not offer any additional protection to prevent the transmission of malicious emails (also known as spam) or files from their networks, as a result, when that happens, their IPs are blacklisted. Emails sent from a server using an IP in the blacklist are marked as spam at the receiving end.