An example of what can be done with it - https://melongaming.com/games/melonjump/ (hold the left mouse button down and move your mouse to play).

More here https://www.melongaming.com/en/Games

The thing I noticed with most JS game libraries is their inability to display text without being slightly blurry. Is there a fix to the issue?

I noticed this in the game you linked as well.

Look into msdf rendering for text in WebGL. https://github.com/Chlumsky/msdfgen