No. They were certainly similar, but KotOR had:
-Better/more engaging side-quests (The Sunry murder trial in particular is an exceptional example by Bioware standards - in a good way; the mysterious box quest and the Yavin Station DLC also spring to mind);
-The originals of several of the characters mercilessly and rather badly cloned for ME (Carth [Kaidan] in particular, but also Canderous [Wrex], Juhani [Liara, etc.);
-An element of actual C&C (albeit not much, but this is Bio);
-Better dialogues;
-Greater variety in quest and level design (Consider the differences between, say, Manaan, Tatooine and Korriban, and the differences between any three of the planets in ME);
-Better voice-acting (This is debatable, admittedly, but KotOR wins by not having Male Shepard in it);
-Better party members (Jolee in particular);
-Better reason that you're SPESHUL;
-Better plot, (see also: SPESHUL).
Like I said, it's the better game. The one edge you might argue that ME has is its combat system, but given how your party members are balanced in such a way that your experience of how balanced combat is varies wildly depending on your class, this isn't quite as good as some might make out. Mass Effect's side quests are so banal and generic that they might as well have been procedurally generated. (Collect ten of X from planet Y by travelling to it and clicking on it!)
Perhaps for an encore we can argue over whether MotB is PS:T and vice versa?
Actually, I don't give much of a **** about Star Wars; my primary fandom is Dr. Who, but great job judging a book by its cover.
I chose this username when joining Filefront four years ago and looking for Jedi Academy mods, if you must know.
Could you elaborate on that, please?