Pretty big uptick in these type of threads lately.
This is not a Mautic problem. I always wondered if posting here about email deliverability issues is an outright proclamation of laziness or disregard for the sophistication of email deliverability. (in my personal unsolicited opinion)
A search of this forum yields @joeyk and @devsrealm sharing valuable expertise on the subject here: Problems with Emails going to SPAM
Those dude are the real deal
And Google gives you: All This
Good Info
This is cool
Nice
This is Rad
Have a good day!