Can Minecraft worlds be unplayable or even gone by playing in the beta on the Xbox One, by leaving the beta afterwards?

I joined the Minecraft Beta on my Xbox One, but would like to leave it again.

My friend told me that if I leave the beta, I might lose the world I started in the beta.

That's why I wanted to ask if someone can tell me if I can still play normally or what will happen to my Minecraft world on my Xbox One (Bedrock Edition).

I appreciate any help!

Usually the world stays normal, but in the most rare cases it is lost.