The loss of half of the MBTI categories is not a serious problem, as demonstrated by the fact that you can't even name the ones that were left out without going back and looking.

Maybe an ESFJ couldn't. Any INTP with an IQ above 50 who is vaguely familiar with the system could write them down after a few seconds thought and a glance at the ones you provided. It's a set of four flipping axis with each extreme given a letter. The names are a plain enumeration.

Seriously, when was the last time you met an ENTP?

I saw my sister last week.