The VTGate proxy server advertises its version as MySQL 5.7.
MySQL versions 5.6 to 8.0
With MySQL 5.6 reaching end of life in February 2021, it is recommended to deploy MySQL 5.7 and later.
MariaDB versions 10.0 to 10.3
Vitess supports the core features of MariaDB versions 10.0 to 10.3. Vitess does not yet support version 10.4 of MariaDB.