as far as game mechanics go rimworld lack building on multiple z levels and fluids.
and then you have gnomoria....
the real differentiation is the depth world history that df has that's quite unique.
I love dwarf fortress, but let's not put that on a golden pillar.
Again, for a lot of DF players that point is lost. They want to set up their efficient workflows or build their wonderful creations or they want to slaughter wave after wave of goblins. However, DF is set up in a way that the player is not necessarily important to the world. You die and the world just continues. You explore the world as an adventurer. You get killed by a duck. Life goes on. Your fortress falls to a weregopher. Life goes on. You explore the ruins of your fortress, track down the weregopher and get your revenge. That's DF. Rimworld has none of that.
Rimworld is a good game. DF is more like a toy.
There's an amazing channel on YouTube, called Kruggsmash, that does DF lets plays. In his current series, he initially founded a new settlement based entirely on bee agriculture and trading - no fighters. He kept the population small so they were under the notice of the local goblins, and got set building an awesome looking place with custom bee related statues, engravings and the like. Unfortunately the other dwarf settlements around him (NPC ones) die off because of the local goblin fortress, and refugees start flocking to his settlement. (SPOILERS AHEAD!) He ends up throwing a vampire goblin down the well, and stabs him with spikes which ends up bloodying the water. The dwarves that drink the water then end up turning into vampires themselves, so he now has a fortress of vampire dwarves! He also has a massive prequel to this fortress series where he plays in adventure mode as a boar man and his compatriot goblin buddy (the one now down the well...), going around stealing artefacts and building his own role-play story, with some amazing illustrations to show what's happening in through all the ASCII graphics.
Honestly, he's more than worth a watch. You get very attached to all the characters, especially the dwarves that have been there from the beginning. He's one of the few YouTubers I've ever contributed towards on patreon.
Rimworld took DF and removed all the innovative elements to fit it into a more traditional base building game. Then yes, if you restrict yourself to some very specific elements of gameplay they can be comparable but you don't play DF for the production chains.
That said, wake me up when you find that your engraver has engraved a room full of images of rats, out of spite because he doesn't like the noble who owns that room.
Or when your Rimworld character, when trying to build a well, gets swept away by the current, scratches himself against the bottom, and now you have a full colony of vampires. Because it turned out that character was actually a vampire.
* No liquid simulation (water/lava) with little physics simulation (falling/flying objects etc)
* Simplistic combat simulation
* No world politics simulation that dictates what happens in the world
* No 3D is the biggest one. RimWorld is Dwarf Fortress as it was a decade ago with a single 2D sheet.
* true, mentioned it
* not really, you get layers and damage type and bleeding and organ failures impacting pawn abilities
* not really you can do diplomacy in rimworld between the colony and factions and it's deeper than current fortress mode options. diplomacy in worldgen is non actionable.
* true, mentioned it
the issue is 4/5 of those thing you repeat from my post don't add to gameplay (fluids) and some detracts even (path has severe issues caused by stairways).