I agree. Black Flag got s lot of comparisons to Pirates!, but while it was pretty great (tailing and land missions aside), it didn't come close to the sheer freedom of this game.
I think the closest modern games have come to scratching that itch have been indie rags-to-riches warband simulators like Mount & Blade, Kenshi, or Starsector, though none are a perfect successor.
I've been playing Airship Kingdoms Adrift, and while it's got some definite jank, it has a similar feel to Sid Meiers Pirates. Not the best, but the closest I've found.
Played the C64 version at my buddy’s a lot, and eventually played “Pirates! Gold” a ton on my AMD K6 200mhz.
There was a lot of gameplay depth there for a game that originally came out in 1987, and it informs more of my knowledge of Caribbean geography than it really should.
"Pirates! Gold" brings back some nostalgia. A friend of mine had the Sega channel when I was in middle school and that was one of the offerings one month. We stayed up into the wee hours of the morning playing that game for hours. Sword fighting and searching for buried treasure. Those were some good memories.
Same!!! We stayed up all night playing this game non-stop over the summer in Sega. We would play Mario Cart until our fingers hurt and then switch to Sega and chill for the rest of the night.
I cannot bring it to play on the Steam Deck, sadly. The game was a good childhood time sink, I used to hang at a friend playing this and we sometimes would switch the keyboard for a mission or ship or something.
Man, I played this game so much as a kid - the ship and sword fights were awesome, the dancing was easy enough once you learned to read the animations (the women actually showed you the moves with their hands!), and hunting down the top pirates was AWESOME (even if I never finished it all).