Hello dear!
That is one of those everlasting topics of discussion among fandom, I assume. 🙂 There are those who think the episode implied that Sam and Dean are soulmates and there are people who think the episode emphasized the opposite. I can’t count anymore how much fighting I have seen about this particular topic…
I personally think that the episode rather strengthened that Sam and Dean are not soulmates as I have argued a couple of times before (see here). And that has nothing to do with what I ship or don’t ship, but only how I read the episode and to me there exists a decided difference between for example us seeing Jimmy and Amelia Novak sharing a Heaven and thus being soulmates and Sam and Dean. Dean and Sam imo do not share a Heaven since they are both in their separate memories and not in one and the same. Sure, Dean was able to find Sam after he remembered his death and Cas set him on his path, but it is highly doubtful that Dean would have set out to find Sam in his memory and Heaven had he not remembered dying and getting told to look for Sam.
So imo Dean was able to access Sam’s heaven because he followed the axis Mundi that runs all throughout Heaven and connects the individual heavens, but it does not mean they are soulmates as I personally understood soulmates to be people who share the same memory and therefore are united in the same Heaven like Jimmy and Amelia Novak. That wasn’t the case with Sam and Dean and furthermore the entire episode focused on the differences between the brothers and how Dean in some of Sam’s greatest hits wasn’t even present.
I hope this post will not launch another avalanche of fighting on this topic. ;P Just live and let live, headcanon and let headcanon.