This is SO bold that I have to imagine it's a sign of a very very significant intelligence advantage Russia has over the USA. They're not going to do this in an attempt to get the US to attack the ship to escalate conflict. They're likely prepared to lose the ship to US violence, but that contingency is likely counterbalanced by a gambit to reduce the USA's diplomatic power by allowing it to erode it's legitimacy. It's also telling that this is happening at the same time that China is reported to be engaging in "intense diplomacy" in LatAm this past week. It feels like a concerted effort to significantly reduce the USA's sphere of influence in a very short period of time, which is only something you would try if you had serious preparations, intelligence, and counterintelligence indicating that now would be an advantageous time.
One alternative is that its desperation, but I don't see a lot of evidence for that.