online-mode=false does nothing

I want to create a private Minecraft: Bedrock Edition server specifically so my kids can play Minecraft: Bedrock with their cousins who don't have Xbox Live accounts. Unfortunately, they are unable to join despite online-mode=false in the server.properties file due to not possessing an Xbox Live account. Because online play is essential to the Minecraft experience, and this setting was likely added specifically to prevent this situation, I assume this is a bug.

Thank you all so much for making such a wonderful game!