This has been happening for at least 5-6 years. There were attacks on Tankers when I was hanging out in the Gulf in 2016-17, and there were some more around the time that the Iranians hit the Saudi pipelines. I recall some in 2019 as well, during the tensions around Trump's sabre rattling. It's a reasonably common occurrence, and the worst I have heard of is one lucky hit disabled a smaller tankers main engine, and it had to be towed in.
Additionally, the Houthi's have, and use, drone boats full of munitions to attack shipping in the Red Sea and Gulf of Aden.
In any case, while it sucks for the ships hit and probably bears watching, it doesn't herald a new and distinctly different threat against shipping in that region.
