Questions about SimpleLogin

Hi everyone. I’m thinking about using SimpleLogin but I have some concerns regarding security and privacy. When using reverse aliases, emails pass through SimpleLogin’s servers—I read they use Proton and UpCloud servers. If you’re sending an email with sensitive information, wouldn’t this pose an additional risk? According to what I’ve read in SimpleLogin’s security policy, they claim they don’t store any emails once delivery to the recipient has been completed. I hope someone who uses this service can shed some more light on this and other related questions. Thanks so much to all of you.