The story is underwhelming, it's absolutely not a "spiritual successor" to it's namesake, and it's not super long.
That said: it's a really really fun FPS single player campaign. The guns feel perfect, the almost all of the abilities are meaningful and feel fun, the enemy AI & diversity is damn good (really cool boss design imo!), and it looks/sounds cool as shit. I also really dug the multiplayer (servers are still up; it's a collaborative L4D type that also kinda feels like ME3 in the core loop?) but that's a bit more polarizing.
If it's on sale & you like "don't take it too seriously and just have fun" PC shooters, I strongly recommend it.