Want to understand why MSSQL and MySQL is still Experimental Configuration in the docs

Hi Team 

As per the below document it says the below url string and Driver is Experimental. What that supposed to mean here. Though it is working just want to understand any risk or experimentation still going on. If so Please let us know what kind of experimentation it is. is it Safe to use. 

• jdbc:mysql://localhost:3306/databasename for MySQL and MariaDB (experimental);
• jdbc:sqlserver://localhost:1453;databaseName=name for Microsoft SQL Server (experimental).
• com.mysql.jdbc.Driver for MySQL and MariaDB (experimental);
• com.microsoft.sqlserver.jdbc.SQLServerDriver for Microsoft SQL Server (experimental).

https://experienceleague.adobe.com/en/docs/experience-manager-65/content/implementing/deploying/deploying/rdbms-support-in-aem#:~:text=Support%20for%20relational%20database%20persistence,BlobStore%20API%20is%20also%20provided

And in the technical requirements document it says.Microsoft® SQL Server 2016 is supported. why postgres is not in the list. What type of rdbms supported here ? 

https://experienceleague.adobe.com/en/docs/experience-manager-65/content/implementing/deploying/introduction/technical-requirements

Platform Description Support Level