For standards like SPF and DKIM / DomainKeys, whether they improve deliverability or bypass filters is entirely at the discretion of the validating receivers. It is expected that messages from a sender with a good reputation would be subject to less scrutiny by the receiver's filters. [1] In other words, omitting these standards usually doesn't hurt, but providing them can only help deliverability.
Some other things to consider:
Let us know how we’re doing! Please rate this page:
If you have a question that needs an answer, please contact support. Otherwise, please open an issue in our GitHub! Thanks for helping us improve our docs!