Comment by WorldMaker

EverQuest and Ultima Online had a huge overlap with MUDs of their time. Both in terms of developer experience (parts of EverQuest allegedly came about by starting from a Diku MUD codebase; several UO designers such as Raph Koster had been MUD devs and/or "wizards"/admins) and also player experience (many of the earliest players and their vocabulary coming from MUDs of the day and/or playing both).