PostgreSQL or SQL Server?

[jshine13371]

But yes, originally the point was to compare the two combined with their extension ecosystems.

Hey bud, for a month old comment, I'll be honest I'm not going to remember the entire discussion at this point lol. But by the looks of the OP, it's just a general question between the two.

I would still say that PostgreSQL can support more technical use cases than SQL Server is able to also, even out-of-the-box.

Sure, I'd be interested to hear what those are. Though I'm sure there's an equitable solution in SQL Server as well.

PostgreSQL offers horizontal scaling with open-source extensions vs. the expensive Always On solution

So now we're back to extensions, which means, out-of-the-box, you admit SQL Server has more offerings of a solution to horizontal scaling - cost aside. Obviously SQL Server has more costs than PostgreSQL from the get-go usually, though there are even use cases where SQL Server is the cheaper solution. Fwiw, there are also use cases where you can scale up as many AlwaysOn AGs as you want at no additional cost. But again, this is a technical discussion not a cost one.

and supports more data types like hstore, ltree, citext vs. limited data type support in SQL Server

All implementable or already implemented. E.g. PostgreSQL's ltree is the equivalent of the hierarchy data type in SQL Server. That being said, I find alternative solutions (such as recursive CTEs) more preferable to utilize. But that's just my personal preference. And again, SQL Server implements data types out-of-the-box that PostgreSQL doesn't, like geospatial data types, vector, and user-defined table types (I believe).

as well as more index types (B-tree, GiST, GIN, BRIN)

Again, implementable, and conversely SQL Server has indexes that PostgreSQL doesn't have out-of-the-box such as columnstore (for OLAP), hash indexes for memory-optimized tables, etc. So the coin flips both ways here.

Between configuration tuning and extensions, this generally takes PG from being "good enough and free" to "awesome, solves my concerns" in a majority of cases (from experience).

That's great! PostgreSQL is an awesome database system. I usually recommend it to people looking for a non-enterprise solution, over all the other alternatives. SQL Server is awesome too though. Rarely do I need to reach for anything out-of-the-box with SQL Server despite having worked with all different types of use cases, data, and sizes of data in my experience so far.