The Ramba”m (which, as you know, we don’t pasken like) was talking about throwing oneself on the tzibur which is not today’s typical Kollel man, certainly not in the first few years of marriage. (I said that so Gavra won’t yell at me about tuition breaks.)
Also, the Ramba”m never negated the productivity of such a person.
So no, one can’t use the Ramba”m to avoid being called an apikorus by the famous gemara in Sanhedrin.