Not necessarily. Many people really love MIT for architecture. MIT's school of architecture was the first architecture school in the United States, it has produced alumni like Cass Gilbert (who designed the US Supreme Court building), Louis Sullivan, Charles Correa, and I.M. Pei. It can provide an outstanding undergraduate architecture education.
All I said, was that it was not necessarily the best school for everyone. There is this misconception that part of this process is to go to the "BEST" school. That is of course tosh. There is no best school. What there might be is a best school for each individual. Most students at MIT have an appreciation for or at least a tolerance of Math and Science (which is useful as they feature strongly in the General Institute Requirements). That holds true of MIT's engineers. It also holds true of their economists, political scientists, philosophers, and of course architects. If you cannot stand math or science, then MIT is unlikely to match particularly well for you. On the other hand, the General Institute Requirement also require a minimum of 8 classes in the humanities, arts or social sciences. If you loathe anything that isn't Math or Science, then again, MIT may not be the perfect match.
And that is what the admissions dance is really all about. It is the match between the student and the institution. The match is really what gets you in or keeps you out.
So you asked an opening question: "Is MIT a good architectural school?" To which the answer is unequivacally YES ABSOLUTELY. You then asked a follow up questions which basically said (and I am rephrasing here) "Given my personal interests, do I match well for MIT then." Nobody can know that apart from you.
Good luck with your college search,