(Source(s) from Sefaria.org)
ברכות אביך גברו על ברכות הורי וכו' תהיין וכו' נזיר אחיו הענין. דכל בניו של יעקב היו מצערים את אביהם במה שלא הגידו לו ממכירתו. אולם יוסף היה מצער עצמו כל הכ"ב שנה שלא שתה יין וכמאמרם נזיר אחיו שהיה נזיר מן היין. וזה שאמר ברכות אביך כו' לראש יוסף ולקדקד נזיר אחיו ולא לבניו הנותרים שלא נזהרו בכבוד אביהם ודו"ק.
"The blessings of your father surpassed the blessings of my parents etc. Let them be etc. the removed one of his brothers": The matter is that all the sons of Yaakov pained their father in their not telling him about (Yosef's) sale. However Yosef pained himself all those 22 years (which he did not see his brothers) that he didn't drink wine as it says (literally) "the Nazir of his brothers" that he was removed from wine (i.e. he didn't drink wine since his sale). This is what the verse means "The blessings of your father etc. upon Yosef's head and upon the head of the removed one (Nazir) of his brothers as they were not careful in Honoring their father.
If reason for Yosef receiving his unique blessing over his brothers was because Yosef afflicted himself by not drinking wine since his sale, how does the Meshech Chochma understand this reason in contrast to Rashi on Bereishis 43:34?
:(וישכרו עמו וּמִיּוֹם שֶׁמְּכָרוּהוּ לֹא שָׁתוּ יַיִן, וְלֹא הוּא שָׁתָה יַיִן, וְאוֹתוֹ הַיּוֹם שָׁתוּ (בראשית רבה
And they became imbibed with him: but from the day they sold him they had not drunk wine nor had he drunk wine. That day, however, they drank wine (Genesis Rabbah).