Well I did set one up today and the mails land in the spam folder for GMX, GMail and Microsoft (@live.de), although I set up SPF, rDNS, and DKIM. I have to take a look at how to setup DMARC, beacause my domain hoster doesn’t allow free configuration of the TXT entries, you have to use templates and there isn’t one for DMARC
iodéOS here and I can’t find it on my phone either (yes I looked at the system apps)