Go and the go std lib are licensed under a bsd license, which is a more liberal license than java and the jdk and would avoid things like the oracle lawsuit against android.
So yes, just because it's open source doesn't mean much, but it's open source with a very liberal license, which does mean something.
Originally, the Oracle lawsuit had some patent claims in it, IIRC. They were thrown out though. I can't recall if they were thrown out by the judge or if Google spent the time/money/lawyers to get them invalidated.
IANAL, I don't think that's true for the Apache license, because it includes a clause that explicitly reassigns patents (or at least licenses any relevant patents).
So yes, just because it's open source doesn't mean much, but it's open source with a very liberal license, which does mean something.