While you are wearing Elytra you glitch through blocks quite often. I first tried to recreate it while going up a ladder since I saw it happen but couldn't. It also can happen while swimming with elytra on. In this video is how I was able to recreate said glitch. Sometimes it doesn't do damage but blocks like stone makes you take suffocation damage. Not sure what other versions or platforms it effects since I'm playing on switch. https://youtu.be/ppVaNZiv6g4