WIY: I don’t know what “halachafortoday’ is but there are signifciant mistakes. R”Moshe zz’l (nor anyone else) “paskens” that the mechitza has to be three amos high. That is absurd. Additionally, you better show me the pask and the sources that say that a mechitza is a must for anything else besides “tefilah”.
I don’t have R’Moshe’s teshuvos handy but there is no source that a mechitza is “mideoirasi”. The whole sugyah is discussed in gemoro sukkot and the source is “novih” not de’oraisa. So, your sources are very suspect and so is “hanachafortoday”.