Oh woah this looks great. Quite amazing they put the effort into this for Postgres instead of SQL Server. The demand must be a lot higher.
MS SQL server is a legacy system. I don't think any business would create a new database using SQL server unless, for some technical reason, they don't have any other option.
I've helped create apps that support millions to hundreds of millions of revenue on Azure SQL Databases that cost at most a few hundred dollars per month. And you can get started with a S0 database for $15/mo which is absolutely suitable for production use for simple apps.
Unfortunately, I think Microsoft realized how good of a value the DTU-based model was, and has started pushing everyone to the vCore model, which dramatically increases the barrier to entry for Azure SQL Database, making PostgreSQL a much more attractive option. If Microsoft ever kills off the DTU purchasing model of Azure SQL Database, I likely won't be recommending or choosing Azure SQL Database at all going forward. It'll 100% be PostgreSQL.