I doubt it's bad blood, I just think the SW is a solo show now and he is interested in picking and choosing band members.
Also just because you're in a band doesn't mean you have to be best friends.
Hmm... yeah, now that I think about it, SW is definitely not the kind of guy I can imagine sending Christmas cards to his ex-bandmates, even if they didn't part on bad terms.
I mean, I don't care about the gold disc thing one way or another, and it kinda sounds like Steven didn't either, so he didn't make a big deal out of a thing that wasn't a big deal, but maybe Marco's grievance was legitimate. What people are taking issue with was the way he dealt with the grievance, where he came across quite poorly and kind of soured some people's opinion of him.
You have to remember that this isn't an isolated incident, if you think about Marco's comments around the time the DT drummer doc came out. IIRC he complained about the way he was portrayed in the audition videos or something like that, and at the end of his post he basically said "fu DT
". Again, he had a right to be angry, but the way he expressed it was pretty unprofessional. When you're doing session gigs for a living, you should be careful with how you portray yourself in the social media, because some artist may be looking for a drummer and even considering Marco for the job, but then they see all this stuff and think "nah, this guy is nothing but drama" and get someone else instead.
I'm just speculating, but I bet this gold disc incident (pun intended) was just the straw that broke the camel's back and that there's been some tension between SW and MM before. Remember when Marco posted that pic of the two of them from some award show and said he "
used to" play with Steven? I think this article sums it up quite well - they've got totally different personalities, so they were bound to clash sooner or later:
https://progressivemusicplanet.com/2016/12/03/steven-wilson-vs-marco-minnemann-a-study-in-personalities/