Zardnaar
Legend
Has some naval combat does not make it Pirates or not Pirates. Nor does it make it Naval. It's just something that might happen (and can be handwaved around if your ruleset doesn't support it). The Pirates genre stems entirely from Treasure Island, which does not include any naval combat or piracy. The Naval genre stems largely from Hornblower, and will involve themes like rank, position, responsibility and duty (naval combat often plays a larger role, and pirates are always evil).
Spelljammer, for example. You might run a Pirate themed campaign, with treasure hunts, lawless frontiers and a hostile lawful stupid navy. Or you might run a Naval themed campaign, with PCs as dutiful officers in said lawful stupid navy (notably, protagonists in this genre are never enlisted men). Or you might do a planet-of-the-week exploration themed campaign. Also, it has terrible ship combat (in any edition), which is best avoided whatever your campaign's theme is.
I included a list of stuff a bit more up to date than Treasure Island.
Most of the major pirate games and pop culture stuff last 20 years.
Its like youre incapable of even comprehending other people's views or why people may indeed expect naval combat in a pirate game lol.
Its very common in modern pirate pop culture is why.