I agree with your point that this is a lot like the pleat argument. It is an awful like many arguments where people want or need to establish claim to something. Why? I don't know.
The arts are here to be practiced, no matter what we call them.
Why? That is a good question. It is of course, very important to practice, practice, practice, and being a serious student also means doing your homework. One can either just do what they are told and follow, never rising above a mediocre level, or one can take the initiative to find out on their own by asking questions such as these. If one is serious about Aikido, then it is of course natural to want to know what the name means. However, many are right when comes to the fact that just knowing what aikido really means isn't going to lead to some grand enlightenment where the essence of aikido is revealed. But it does lead to more questions, which is important. Now that we know what ai, ki, and do really means, we will want to know more about it and practice even more.
We must practice, but we must also learn.