[NOVICE] IDE/Platform question

Hello all,

First, I'm not a programmer OR a DBA, I'm a general purpose sysadmin,
but I am sitting in on preliminary discussions regarding a new
application project that will be dealing with a LOT of data, and will
need to be able to scale out (ie, SaaS) well, and be performant.

This will actually be a rewrite of a failed earlier project that used
ASP.NET is running on Windows Servers, using Microsoft SQL-Server as the DB.

I want to recommend that we use PostgreSQL rather than SQL-Server, but I
am fairly sure that the developers will want to use both Visual Studio
(not sure if it will be the free VSCode, or the full version) and the
new .NET core that will run on linux for the framework.

So... is there decent integrated support for PostgreSQL in Visual Studio
and/or for .NET Core? Any suggestions for a different IDE that would
have better support for PostgreSQL?

Would also appreciate some tips/pointers for how I might be able to
persuade them from sticking with a Windows centric solution, especially
for the SQL DB side.

Thanks