Kaido was losing at start of his career, Rupee is losing at the end of his career. Difference.
You don't even know when he lost. Besides, Luffy is nowhere near end of his career. He is still growing, lol. He is just 19 year old. Kaidou and Zolo were worse than Luffy at that age.
Yes, Zoro is the strongest since plot doesnt have to turn heaven and earth to make him win, like Rupee needs.
Okay.
Plot saves him from many embarrassments, opponents won't go all out. Powerups with epiphanies. Yeah, sure he does not have plot armor and Oda doesn't turn heaven and earth to make him win.
No 2 of the strawhats will always be #1 when it comes to strength, just like you saw it with your own eyes on the rooftop.
Lol, from what I see in the one piece, it was not the case. Poor soul only you can see something that was not the case in one piece. Not Kaidou, not others. Not even Zoro himself see what you have seen.
No. 1, lol. Oda directly answered you in SBS, but that doesn't work for ya. Worst case you have Luffy and Zoro equal in strength in old age VC. Anyways, live in your own lala land.
PS: It is Luffy not rupee. Maybe the fantasy piece you read has rupee but in One piece, it is Luffy. There itself it is conclusive evidence that you have not been reading one piece.