Question

To my revered teacher, may he live long and well.
Following a conversation with the Rabbi about changing Jewish law, I went to check Maimonides, Laws of Rebels, chapter 2. There he writes that in a case where the Sanhedrin thinks its predecessors erred regarding Torah-level law, it can change it. This does not apply in our day if people want to change the Jewish law, for two reasons.
1. We are not expert in the methods of exegesis.
2. It is permitted to change only if the earlier authorities erred in the interpretation, and not for other reasons.
By the way, Maimonides himself writes in his introduction to the Mishnah that the basis of Torah-level laws was given at Sinai.
And moving from one topic to another, if I have found favor in your eyes, I will trouble you with another question about morality and Jewish law.
Isn’t Jewish law really the main thing? After all, even in commandments between a person and God there is the idea of “and you shall walk in His ways.” The Holy One, blessed be He, does not like those who find a halakhic loophole in order to escape His commandments. The same could be said about the moral dimension. In essence, aren’t the laws just the practical part that was given so as to know how to fulfill the commandments, or morality? By the way, is it possible to command a person to be more moral than Jewish law requires, for example to be vegetarian?