Too many ethical issues to perform in large numbers. The fact that it is a surgery is a minor problem(although I will recognize it is a very minor surgery). Even further, even though men can result in unwanted pregnancy, a large number of men do not, and so to force them to undergo this kind of surgery is problematic. In addition, there is a problem in the large-scale storage of biological material, AND in making sure that this material is properly protected. A man's body is something easily kept together, but a storage facility could even result in nightmarish misfiling issues, thus resulting in men who have false sperm or who no longer have their own sperm(which is an issue, particularly in that mating selection is implicitly a selection process for good genes). Or as well, have problems in that large quantities of semen will have to be shipped for people who move across the country and/or world(or large numbers of people). In addition, human beings may like the idea of conception, which, conceiving a person from a laboratory decision has less magic than deciding in privacy in a bedroom and through a sexual act, sex and fertility have generally been subject to human rituals and seen as "magical" and this removes the "magic"(Note: I am not referring to mysticism, only an aesthetic). As well, men may enjoy the feeling of ejaculation, which, no longer exists if they have a vesectomy. And as well, there are all sorts of issues with violation of "rights", and with immigration, as immigration may plummet or emigration may rise because of a policy like this, as mandatory surgery with life-altering consequences is pretty draconian. This policy will harm the lower classes more than any other class as transportation of semen will either have to be tax-funded(making it unpopular) or it will involve financial costs for conceivers, which will impact people on grounds of their socioeconomic position, even when this does not impact desirable traits. (Many people with advanced degrees also fail to attain high levels of wealth) Finally, population growth will go down, which.... generally isn't good for fiscal matters, and it really isn't even that important for the first world ANYWAY, as most population growth is in the third world. (as well, given that this is a massive change, we do not know the socioeconomic impacts, thus making large-scale implementation very dangerous as there can be many unforeseen consequences)
Finally, sex ed is still needed because one of the REALLY big issues isn't pregnancy but rather STDs. STDs can be irreversible, but unwanted pregnancy is reversible, and/or temporary. A woman doesn't have to keep the child once pregnant, they can put up a child for adoption. A woman doesn't have to carry the child to term. STDs, however, can lead to death and/or permanent health problems, and they are a major concern with sexual behavior. We will never be able to abolish sex ed.