As a partner and « power » user of brevo i have onboarded quite some customers. Many of them use brevo as a transactional mail provider due to the great gdpr compliance. However, I noticed mission-critical issues that were raised to the support and on your partner slack before, that push as to the edge of using other providers.
The biggest issue we currently face is that each transactional mail has a « List-Unsubscribe » header added automatically. We have no documented way to control this behavior, and it allows customers to unsubscribe from mails like password reset or 2FA notifications. It is really hard to get my head around how this could not have been noticed or tackled so far.
The other also major issue is that there is no way to disable link tracking. This is not only critical in an event where brevos redirection service is down. (Currently the case) It is also a major issue for gdpr. For marketing mails, you get the opt-in of customers, but transactional mails are sent as a requirement by platforms. To make this process as compliant as possible, links should not be tracked. At least give us the option!
I would really appreciate some feedback. Feel free to provide documentation in case i missed something, I will happily correct my thread 
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