Point of note, MoE was one of the best selling adventure games of its year. It outsold Grim Fandango 2-1.
Only problem? Adventure games in general were failures that year.
So in general it wasn't MoE fault it was the fault of Adventure Games industry, and the public. Adventure games just weren't as profitable or enjoyed by the masses at that time. Adventure games demographic was too limited to be profitable.
Infact adventure games still have a limited demographic.
According to one interview Roberta Williams claimed it sold comparable well to previous King's Quest games, at least as well as KQ7 did.
Only problem what she would have considered successful, had her husband still owned the company was not considered successful by Sierra's owners at the time. Havas Interactive, IIRC.
BTW MoE is nothing like doom it has more in common with Tomb Raider style games. Yes you could play in first person but it actually worked better in 3rd person. Plus all the puzzle solving was very much tomb raider inspired.
The battle system itself was more "diablo" like point and click killing. Although it also had some similarities to QFG5 battle system as well. The designers though claimed Ocarina of Time, and Super Mario 64 as inspirations. Which also had some what tomb raider style puzzle solving in parts.
