Do you ever send mails to Gmail and Office365

All the time, never had an issue. I get dmarc reports constantly since I set my dmarc to notify, not just failed, but I’ve never seen PTR checked on Microsoft or google. It passes SPF and DKIM (presumably spam but you don’t get a report for that) and they let it through. I used to think it was because I’ve had most of my domains for a long time, but the couple times I’ve brought a new domain online, they seem to be fine with them.

Now they might be passed because my old domains have never had an issue and they get associated because they come from the same IP?

My ISP would let me set a PTR if I wanted but I haven’t bothered because it doesn’t seem to be an issue.