77 I think the most fundamental difference between Rimworld and Dwarf Fortress is in the number of units under your control. In Rimworld, you start with three colonists, and only occasionally get more as you capture invaders and recruit them. In Dwarf Fortress, on the other hand, you embark with a band of seven dwarves, get regular waves of migrants, and can easily reach the cap of 200 dwarves in a matter of years.
In DF, you have plenty of peeps to have them all specialize in tasks such as mining, smithing, growing, brewing, etc; whereas in Rimworld, you have so few colonists that you don't have time or personnel to dedicate everyone to their own tasks. In addition, there's just not time in Rimworld to smelt all your ores, or smelt iron ore three times just to get steel for all the things that need it, which explains the lack of diversity in Rimworld's minerals.
Also, since there are so many fewer colonists in Rimworld, you can afford to micromanage them much more closely than in DF. In DF, you have so many dwarves that assigning priorities for all their tasks and when they should sleep, work, or have fun would simply become infeasible. In addition, the more populous Dwarf Fortress allows you to train up a dedicated military- there's no need or really any good reason for your civilians to pull double-duty, unless you just want everyone to wear armor all the time (which has its advantages).