The default flavor is the upstream supported version. For older ARM CPUs we have an -armv80a flavor now. MongoDB is known to be used by net-mgmt/unifi* users on this hardware. MongoDB 6.0 is planned to go out of support in July 2025 [1], so this is preparation to make MongoDB 7.0 the default dependency for Unifi. [1] https://www.mongodb.com/legal/support-policy/lifecycles