Oda sowed a lot of parallels between Luffy and Kid during the Wano arc.
The portrayal of Luffy and Kid being equals seem so obvious:
1- They Both have the same dream to find the One Piece and become Pirate King.
2- Both have come face to face with 2 Emperors of The New World. Kid clashed with Shanks & Kaido while Luffy clashed with Big Mom & Kaido
3- Both are wielders of all 3 types of Haki including the rare Conqueror’s Haki.
4- Both have clashed and defeated a Sweet General of the Big Mom Pirates
5- They both have 1st Mates worthy of a Worst Generation title
6- They both were able to resist being mentally & physically broken in the Udon Mines.