The problem with this question is that there is a ton of stuff you need to understand before you can really answer that question fully. To know what public means, you need to understand classes, and visibility rules for classes. To understand static fully, you kind of need to know how c++ works, since it's equivalent to a bare function in a namespace. Void is the type of the return, which means it doesn't have so that's pretty straight-forward. Main is the name of the function that gets run when you run the program, which kind of requires knowledge of program entry points (assembly) either that or the understanding of what a library is. The simplest thing you can say is that it's boilerplate to signify what function gets run when the program starts, but that doesn't really explain any of the pieces.
There are many more languages that implement a "Hello, world!" with one line of code. If explaining "public static void main" is too hard, maybe one is using the wrong tool.
So the first language should be one that gives the student a firm foundation from which one can become that competent.
I've personally seen excellent introductions to programming using C (CS50x), Python (Think Python, MIT 6.001), and Scheme (SICP).
I'm so glad I learned Lua before taking APCS, otherwise that class probably would have set me back 6 years.
For me and probably many others having it go unexplained was like dangling carrot in front of me. I went home and read more about it.
Which is why Java is a terrible language for an introductory programming class.
For a particular kind of curious student, "just do it because you have to" is a very fast way to them checking out and doing nothing at all.
They will dissect, examine and research it on their own and their learning will be much deeper.
Self learning is the opposite of the classroom issues I had. I can start a webpack tutorial, it'll mention Make, and I can click links and chase down information, and just keep my stupidly ADHD brain entertained with more and more new new new things. This is how I have to learn things, apparently.
If a student is going to 'check out' because they didn't get a question answered, then they're probably just going to fail. See your teacher after class, ask a friend, look it up online... If are a 'curious student' doesn't see these very obvious methods of satisfying their curiosity, then they're probably not worth a teacher's efforts.
Python is even worse, because it's so high level and so much happens 'by magic'. Don't get me wrong, it's a great teaching language because it does cover so much ground, but it's terrible as a first introduction for a new programmer.
They need to start with something simple and fairly concrete. Maybe even start with a simulated 'toy' assembler (first semester CS101 = Zachtronics games?) then something like Pascal to teach the basics of control flow and sequential processing.
Once students understand primitive data types, control structures, functions, and compound user-defined data types, they're probably ready to learn some OO.
Take the Javascript course - a fantastic way to get introduced to the syntax of the language, and I highly recommend it for total noobies. But then you come out of it with no understanding whatsoever about what javascript is. If I asked someone who just finished the course to make an "app" that console.log'd to the console, they wouldn't understand where to start. They wouldn't know that JS is a language run in the browser, that they need an HTML file with a script tag or a node file that they can run in the terminal. They wouldn't know about DOM manipulation, etc.
This reminds me of the Java class I took in highschool - the teacher was going on about ints and floats and loops, and the only questioned I wanted answered, and never got an answer for, was "what does `public static void main` mean?" I think the fact that I never got an answer to questions like that are why it took me nearly 3 years into my career to figure out I should be a developer.