How is giving gifts a messianic prophecy?
Is this a joke???
And this psalm is not about giving gifts, it is about receiving gifts! Ephesians 4:7-16 speaks of Jesus giving gifts -- so it is the reverse of T'hillim / Psalm 68:19 (18 in Christian versions which either do not print the first line, or do not number it) which says "You ascended on high, you took captives; you took gifts to be among men, and also rebellious ones for Yah G-d to dwell."
"You took gifts."
Not gave them.
Did you notice "you took captives"?
Jesus never took captives.
The Psalmist is also speaking of something that already happened (not a prophecy of something that will happen).
T'hillim / Psalm 68 is G-d triumphant, taking care of orphans and widows and overcoming the enemies of Israel. Indeed, the psalm is reminiscent of Deborah after the victory of the Israelites over Sisera, general of
Jabin (Shoftim / Judges Chapter 5). R' Kimchi (1160–1235), known as the Radak referenced Shoftim / Judges 5:26 in relation to line 8 of this psalm.
Are we in bizarro land where the list maker is making claims based on the reverse of the biblical text s/he is referencing? It certainly seems so!