וַיֹּאמֶר חֹתֵן מֹשֶׁה אֵלָיו לֹא־טוֹב הַדָּבָר אֲשֶׁר אַתָּה עֹשֶׂה׃
But Moses’ father-in-law said to him, “The thing you are doing is not right"; (Shmot 18)

The Halachah says (Rambam T"T 5,9):

רָאָה רַבּוֹ עוֹבֵר עַל דִּבְרֵי תּוֹרָה אוֹמֵר לוֹ לִמַּדְתָּנוּ רַבֵּנוּ כָּךְ וְכָךְ. וְכָל זְמַן שֶׁמַּזְכִּיר שְׁמוּעָה בְּפָנָיו אוֹמֵר לוֹ כָּךְ לִמַּדְתָּנוּ רַבֵּנוּ.

If one beholds his master transgressing the words of the Torah, he should say to him: "Our master, you have instructed us such and thus." Whenever he quotes a lecture in the presence of his master, he should say: "So have you, our master, instructed us."

Moses just descendent from 80 days of continuous learning Torah from G-d Himself and some freshly converted old man judges his behavior publicly.

It is clear that Yitro comes not against Moses as a person but against the whole Torah and its scholars.

How Halachic is it, and if not, who criticizes Yitro for this conduct?