I have no problems with Gmail from Digital Ocean. But I have both spf, DKIM, DMARC and a reverse pointer. You need to not look spammy.
One advantage to using a VPS is your IP is unique. That is you don't share it with a spammer. Not so with hosted services.
Original Message From: M.Roos@f1-outsourcing.eu Sent: October 26, 2020 1:06 AM To: dovecot@dovecot.org; sebastian@sebbe.eu Subject: RE: SV: Looking for a guide to collect all e-mail from the ISP mail server
and also the problem is that gmail imposes heavy spam filters and "reputation blocks" meaning smaller providers with low email volumes, are put in the spam folder, even if they never send spam, just because their email volume is so low (ergo, they must prove they don't spam before getting out of ispam folder)
How do you know that?