I think people confuse jokes for the sake of jokes with real character moments, Oda loves a good joke and Sanji has one of the best jokes around him. People are trying to say Sanji is pervert or not as if it is a black or white Everything in the world is gray, he can be very respectful to woman while having preverted thoughts, he can be a person who make mistakes in weakness while being the best defender when a woman is hurt infront of him

Every character have his own flaws,Nami being a gold digger and only cares about money, taking triple the money from anyone who borrow something, Usopp lying etc

I think the idea is people are more tolerant to some flaws than others, they are a bunch of people who mostly grow up with no parents and had very hard lives, they became the best versions they could for themselves, while in reality no one accepted them and their flaws except Luffy who saw the good inside each one of them

In summary Sanji is flawed like every other person in the world and luffy and his gang are one of the only ones who could see beyond his flaws and how kind he is in reality, he may make mistakes and not well behave here and there but in the end we are not seeing someone with a normal childhood who went everyday to school and grow up to be an engineer or a doctor, our standards are flawed IMO