Probably fine, just worried about possible side effects. I support trying it out, but at the same time it feels a bit strange to me as we are “personalizing” the email address so the odds of someone seeing it and assuming that
meta+sam@discoursemail.com
is somehow an email they can use to reply to Sam.. is much higher now versus
meta@discoursemail.com
Thinking about this a bit more I feel this is kind of a nasty hack and has the possibility to do more harm than good.