I'm not playing it but I'm pretty confident it's not an MMORPG. Read what one of the game's biggest fans, Keen, says about in a recent post : https://www.keenandgraev.com/2018/03/15/everything-you-need-to-know-about-sea-of-thieves .

He goes out of his way to explain what the game isn't: says "Sea of Thieves is NOT a MMORPG!...Sea of Thieves is NOT a PvE game!...Sea of Thieves is NOT a RPG!" Makes you wonder just what it is, doesn't it?
 

Not playing, but after watching a few streams of it, it strikes me as a sort of team FPS-like game (but in third person view) on a large world map, given a thin veneer of MMO quest flavoring and a hefty helping of comic pirate theme and arcade ship battles.

Basically, you’re always in PvP, the game auto assigns you to servers wherein other players are roaming and the main gameplay element is really duking it up against other teams of players with your own team of friends. The PvE is just something to pass the time, let you earn cosmetics, and ostensibly to give you a reason to go somewhere and thus potentially run into other players.

Chasing and being chased on a ship (while managing sails, steering, anchor and so on), the maneuvering of ships while in cannon range and attempting to sink them or be sunk (and the repair and bailing that delays this), plus the boarding and individual FPSlike pewpew combat with guns and sword seem to be the major thrill-inducing gameplay loop.

When you die, you simply respawn back on your ship, as long as it isn’t sunk. This tends to lead to a cycle of comic FPSish revenge action if teams are equal. If your ship sinks, then your team and your ship respawns on an island nearby. Not sure if intentional or desired, but since the people who killed you are also tend to remain conveniently in the vicinity, you can encounter them again for another brawl.

I think it works well as a casual team vs team game. I think soloing might be distinctly less fun, if the soloer is inexperienced and runs into a team of more experienced players. But I’ve also seen some experienced solo streamers do a 1v3 or 1v4 against patently newer and more inexperienced teams of friends who can’t coordinate as well. Ultimately, you have to like the experience of pootling around on a boat and sinking other people’s ships and stealing their stuff as a means of keeping score like K/D ratio or W/L in an FPS. It doesn’t strike me as very much more persistent a world than some FPSes these days.
 

Sea of Thieves is a role-play game that happens to be online and massively multiplayer. It doesn't fit any of the criteria for being an MMORPG. MMORPGs feature character attribute growth, limited multiplayer interactions and the only roleplay comes from the computer rolling a random number generator.
 

I had the same question, and the idea I have after some search is that is an open-world cooperative adventure, a mix of roleplay and action, a kind of renamed "world of pirates"..
 

You could play it for free for two weeks using XBox Game pass which allows access to PC games too
https://www.xbox.com/en-US/games/xbox-game-pass

 

Given your (Tobold) stance on most PvP games (World of Tanks excluded), or games with heavy grief potential, I don't think you would enjoy it much. I only played a beta stress test, but I can see where the grief potential would be quite high, with not all that much PvE stuff to do.

If you had a dedicated/consitent crew and made up your own role playing, which you do enjoy quite a bit of role playing, it could be an interesting adventure as you make up your own fun and story.
 

Haven't played it, but there are lots of reviews. The impression I have is that the PvE content is lacking, and the PvP is fantastic if you have the right team-mates, but potentially a nightmare if you don't have team-mates or are getting camped.
 

It sucks to play solo and has basically zero progression so I think you'll get bored of it fairly quickly. Story is practically non existent as well. It's more of a sandbox pirate game but suffers heavily when played solo.
 

The PVP is non-consensual - full free-for-all in all areas. What this of course means is that the entire game is a PVP game.

Kind of like how a mug can be 95% full of water, but if there's 5% instant coffee in it, it is now a mug of coffee.

That's pretty much all I needed to know about it.