I do understand the passion for SQL Server on Windows containers, but as you can see the tags and images were not updated in the last three years for various reasons. One of the reason to delete the mssql-server-windows-developer and mssql-server-windows-express repos and images in those repos is that going forward we do not want any new users and customers downloading it. But if you already have it and are using it you can continue using it and also custom build your SQL Server on Windows images but they are not going be supported as was the case with the images on mssql-server-windows-developer and mssql-server-windows-express as they were in Beta mode which was meant for development and test environment's only.