I have a feeling that most "kids" in college are not particularly sure of what they want to study in school or what they want to do when they get out of school (if someone has evidence to prove this, or otherwise please share). Given this assumption, I think that it makes even more sense to take a couple years off before you go to college. But even if this assumption is not true, I still think it makes a lot of sense to not go to college right away after high school. Let me tackle this both ways.
First, given that most kids are not particularly sure what they want to study or do it makes sense to take some time between high school and college so you can figure stuff out. I'm a proponent of being able to take time off, in this case, to explore different interests and career paths or just to party and hang around.
I think it's obvious why taking time off to explore different interests and career paths would be valuable for someone who is not sure of what they want to do. Through experience, someone can figure out what practical things they are good at, what they don't enjoy, and hopefully what they do really enjoy. So ideally, someone who takes time off after high school will go through these motions and get a better sense of the direction they want their lives to take, so when you go back to school you know what you need to focus in on. But in all liklihood, if you let a teenager loose they probably won't do the responsible thing. So let me explain why I also think it's important to take time off even if it's to party/chill out.
After taking it easy and partying for a while, a kid will probably wise up and realize that life is not that simple and will start to take more responsibility and go down the path I mentioned in my last paragraph. If a kid is never able to realize this after partying for a long long time, they probably would never have been able to get that beaten into them through being in the academic system for 4 extra years anyways. I personally know several kids that are really wasting their time in college, so I will extrapolate that there are millions of other students doing this whom I will never know. I define waste as: partying way too much, attending classes only on occasion (or not at all), and/or taking classes just for the sake of taking classes (and not because they are interesting or valuable in any way). These goof-offs are better off goofing-off while not in college. Doing this while in college is a waste of time, money, and a valuable opportunity. A parent will often say something like, "Stop partying and wasting your time! Trust me I know what's best, and what's best is focusing on school work."
Well as it turns out, parents and adults generally do know what they're talking about, but it's hard for us kids to see that as immature creatures. We listen and remember lessons better by learning from our own mistakes and making the decisions ourselves. So even though you Moms and Dads of the world are usually right, we probably won't listen and will go with our own gut. Why not let us go with our own gut, even if that gut says to party? Just make sure we're not in college while we're doing it. Let us waste our time when that time isn't worth $40K+ a year and wait for us to wise up, figure out what we want, and go back to school if we so please.
College can be extremely valuable. You have a wealth of resources from your classmates, to your esteemed/experienced professors, to the great choices of classes and extracirriculars. People would be able to attain much more value out of these resources if they knew exactly what they were trying to get out of them and if people weren't too busy being distracted by other goof-offy things. Therefore to me, it makes a lot of sense that someone who doesn't have it completely figure out yet should take some time to goof off and figure it out before they go to college and extract every dollar of value they can out of the resources there. It'd be much more efficient that way. For very similar reasons, someone who does know what they want to do should also take time off between high school and college.
Now given my first assumption was wrong, if kids did know what they wanted to learn/do they should still be expected to take time off between high school and college. The first obvious thing is that people often think they want to do something before they actually do it. So taking time off gives those people a chance to try it out, and really figure out if they want to do it. If they really did want to do it, well nothing is lost because at least you get some valuable experience out of it. If it turns out that the person didn't end up actually liking what they thought they would like, well then they just saved a lot of time and money figuring it out before they went to college.
There is a less obvious reason for why someone should take time off if that person already knows what they want to do with their life and that thing has a high liklihood of not changing. Let's say I know that I want to be a programmer. Taking time off to try to do that and getting some experience will still be extremely valuable for me because 1) I'll figure out what parts of programming I really enjoy and 2) which parts I really suck at. Knowing both these things will help me extract more value out of college. I will be able to choose which classes to take, professors to talk to, people to interact with based off what I know my particular fancy is and based off what I know I need to learn more about and get better at.
All of these reasons I mentioned about why taking time off between high school and college is good revolve around extracting the most out of college as possible. This should tell you that I am not actually against college and higher education, I am just for a different approach then what is traditionally acceptable. As I mentioned, I believe college has several great resources for people and that everyone should recognize it. The only thing is, I believe that you should optimize your time in college. And I think that for everyone, no matter what your case is, you can optimize your time there by first taking some time off between graduating high school and going to college.
I think that going to college is still generally a good thing so it should still be commonplace for people to attend college. I am just proposing people shift their views about how fast the turnover should be between a student exiting high school and entering college.
Would definitely love to hear your thoughts in the comments!