I think a lot of the rage here aren’t aware of the context.
I doubt it is a post as a dig to Greenwood. If nothing had happened in relation to Greenwood, it would still be very likely Rashford would have posted this anyway.
We have to remember he’s been through a tough personal time as well. He’s just got back with his Mrs after 8 months seperated. He’s probably just sharing his renewed happiness.
You're right. But given Rashford is obviously close to the turmoil in the squad at the moment and I imagine it's being discussed on group chats etc. he would have at least had a moment where he thought - "perhaps this post would be taken in the wrong way" yet he just thought f-it and uploaded anyway. Even if he didn't think this (unlikely) someone close to him would have messaged and asked if this was a dig - at that point he could have thought about it, but f-it it staying up.
So maybe the orginal intent wasn't to have a dig, but it definitley is one and he knows it.
And if it's not Rashford but a social media manager, they know full well what they're doing. Creating discussion, shares, relevance and it's worked.