Is it me ... or does everyone seem to enjoy oral sex A lot???

I'm not trying to be mean. I'm just trying to understand why it's so popular? This goes for either end the receiving and the giving end. I hear some women say, "if you don't do it, he'll damn sure find someone who will." And I also hear some people say it's a deal breaker for them. My question is, if you love someone so much ... Why would you leave them over something that could be compromised or taught or idk (i guess it depends on the person)? Is oral sex a Needed or Essential to sex?
And for the people who say ,"well you should let him know right away or he deserves to know when he first meets you" how do you even expect someone to bring up that conversation or idk?