Articles about that strait being blocked often are illustrated with pictures about a crowd of ships at anchor waiting for the strait being opened again.
Sometimes these vessels shown are typical crude tankers, but from time to time I see pictures (usually credited to Xinhua) of a field of ships at anchor with the following characteristics
Pretty small as oceangoing freighters go
Superstructure takes up a large part of the deck
Shown with high freeboard (they may be all in ballast, and/or constructed to be pretty high)
I cannot find a good article with a static photograph at the moment, the best I can do is the first few seconds of this German newscast video
They are small local vessels that I believe are called - or at least are in the style of - traditional Lenj boats. They are pretty general purpose as I understand it (fishing, passengers, local cargo trading).
They are not tankers.
Ironically while they are being used as background shots for stories about the Hormuz blockade I doubt they are subject to it.
Lenj boats are built by the people of southern Iran and the inhabitants of the Persian Gulf for two main purposes: passenger transport and cargo shipping. They are used for maritime travel, trade, fishing, and pearl diving. Traditionally, Lenj boats are handcrafted using wood.
The traditional boatyards on the island of Qeshm where these vessels have been built for the last 400 years are UNESCO Heritage sites. Qeshm is ground zero for control of the Strait of Hormuz