I don’t think you mean 119:73. The ‘yod’ there is ‘yadecha’ - ‘your hands’.
Probably the vowel points were in use long before Jesus, but weren’t standardized. Somewhat like the teaching that even Israelites in the desert from Egypt made private notes and used shorthand clues as memory aids to Moses’ teachings.
I beg to contradict your minimizing of the inspired issue that this yodh is the letter that begins every word of the following seven verses.
The Psalm is given in verse group of eight, each in the group beginning with the same letter, as they do patterning after verses 1 through 8, for which each verse begins with alef. The purpose of the scheme is for the Hebrew student to learn his alpha betas by memorizing the scripture verses in that order. This is pointed out in the English translations in which language the verse does not begin with the inspired letter.
My Greek instructor is memorizing that Psalm, in the Hebrew. This arrangement certainly helps him.