Usually you don't really know what you want to do in life (or even what to study if you choose to go to university) when you are done with high school. Taking a year to experience new things and enjoying yourself is great excuses to take a gap year.
I took a gap year, got my drivers license, worked, went to Munich for three months to study German. Great time and gave time to figure out what I wanted to do with my life. Or at least partly figuring out what I wanted to do.
From the way your question is phrased it feels like you want to take a gap year, but don't have a reason yourself. If this is the case the answer is simply put: don't do it.
On the other hand if you have some ideas and want to validate them and see if they are worth it, post them and we can give you feedback on them. This way the discussion would be a lot more constructive.
If you're going to take a gap year, you should know what you're going to do and know what you want to get out of it.
In those cases, a gap year is better than just plowing ahead with whatever you're doing (and don't want to do).
For example, a good gap year would be a full-time (or perhaps paid internship - unpaid internships are usually crappy and pay-your-dues type affairs) job at an interesting company in a field you're interested in. So an example would be working at a startup as a software developer or even a business role.
"For the time being, there is no need for either of us to be here. And if that is the case, I feel, it would be better for us not to be here."
I mostly disagree with those who say that you need a plan or purpose for a gap year to be useful. Mostly, because I do think some kind of plan or purpose, however vague, is good, just to provide you with initial and general direction.
A gap year is often exactly the kind of thing that can give you a long-term plan and a purpose, so waiting on these things before you take a year off can be counter-productive.
I used to do a lot of hitchhiking for fun. When I went hitchhiking with absolutely no plan, I wasn't always happy with the aimless results. But when I'd set some initial goal, a random city or country, the result was wonderful. Very often I wouldn't arrive at this initial destination, but see many others instead.
If a gap year is not going to negatively impact you, I see no reason why you wouldn't do it. Even without a plan other than partying!
As a university student you'll have more information, travel opportunities, and potential outside funding than you currently do. There are some organized programs that only take university students. It can be easier to find work or an internship as well. You may know what you want to do better by then.
Good luck, whatever you choose!