You just said why:
Conquistador chooses which OP fans he likes based off whether or not they suck Doffy's dick like he does. That's why he absolutely despises me and, as seen in the comment you quoted, hates people who claim Doffy was power cliffed/creeped. He also hypes Doffy's underlings a lot and believes Doffy's closest underlings like Diamante and Vergo are above the Tobiroppo, mostly to elevate Doffy himself obviously enough.
At the end of the day he's just doing what most other powerscalers here do, mindlessly wanking a character simply because he likes that character. It's the same reason why Nik thinks Mihawk is top 1 even though he himself has said that he also believes Kaido is technically top 1, but that Oda will "suddenly retcon it".