Upd. 04.09.2021 - yeah.

Figured out a way to bundle the project into a single file (my other attempts failed miserably). So, well, you can try making your own players now! Github link. Use the instructions on github and this page's source code for reference, and please contact me if you need help! But please keep in mind that it is unfinished and might not suit your particular needs. I'm open for feedback.

Upd. 15.07.2021 - almost there! Added a few controls and polished out the existing ones. Most importantly, I added a complete demo player that shows that the player is customizable with whatever styles you want! Feel free to explore the page's source code to see how the player is set up and initialized. Perhaps the next time I update this page, the library will be ready for public use.
Below are the two players that were used during development. All the 3 players on this page work independently, and you can, theoratically speaking, have as much players on the page as you want. The left one also shows that any control can have more than one instance.

Upd. 13.07.2021 - added displays for song length, current time and a seeker. This is rather buggy right now, since the pecularities of YouTube's api for requesting a song's length made me rather annoyed, so I just wanted to get over it quickly.

Upd. 07.07.2021 - added support for multiple players on the same page. It was tough and the code is shitty because of asynchronous nature of YouTube's iframe API. I've also separated the monolithic code into files - it might not work in older browsers now, but it will be fixed because I plan on using a transpiler in the nearest future.

This is a demo page for a JS YouTube player I'm working on.

I couldn't find a player that would allow playing videos without actually displaying them on the page; apparently it's against Google's ToS or something - good thing I don't care.

So far I made a display for the current song, basic control buttons and a list of all the added songs with tagging the current song. It is all customizable, of course - I want it to be as easily customizable as possible.

Since releasing this publicly might be problematic, I think I will just leave it here on Neocities for people to use when I'm done.