Deployment file proliferation

---
**Issue moved from dotnet/aspnetcore#23018**
- Please respond to @SoftCircuits.

---

_From @SoftCircuits on Tuesday, June 16, 2020 9:07:34 PM_

### Bug description

When deploying my ASP.NET Core 3.1 Razor Pages web site, I am dismayed by the number of files produced.

This is a small website I've only been developing for a couple of weeks. The root directory has 76 files and folders. It appears there are about 15 language folders (I only need English), and the *runtimes* folder contains a bunch of subfolders that appear platform related (I only need Windows).

```
alpine-x64
linux-arm
linux-arm64
linux-armel
linux-musl-x64
linux-x64
linux-x86
osx-x64
unix
win
win-arm
win-arm64
win-x64
win-x86
```

The deployment uses *Framework-Dependent* mode.

A workaround for the language folders appears to be to set the *ExcludeAssets* property of the *Microsoft.VisualStudio.Web.CodeGeneration.Design* package to *All*.

After trying several other techniques to prevent the platform folders, I have still not found a workaround.

My question is why do I need to find a workaround? It feels like the developers don't really care how many files are in my deployment and so everything gets thrown in there. It's troubling that the developers do not share my values.

### Further technical details

.NET Core SDK (reflecting any global.json):
Version: 3.1.301
Commit: 7feb845744

Runtime Environment:
OS Name: Windows
OS Version: 10.0.19041
OS Platform: Windows
RID: win10-x64
Base Path: C:\Program Files\dotnet\sdk\3.1.301\

Host (useful for support):
Version: 3.1.5
Commit: 65cd789777

.NET Core SDKs installed:
3.1.301 [C:\Program Files\dotnet\sdk]

.NET Core runtimes installed:
Microsoft.AspNetCore.All 2.1.19 [C:\Program Files\dotnet\shared\Microsoft.AspNetCore.All]
Microsoft.AspNetCore.App 2.1.19 [C:\Program Files\dotnet\shared\Microsoft.AspNetCore.App]
Microsoft.AspNetCore.App 3.1.5 [C:\Program Files\dotnet\shared\Microsoft.AspNetCore.App]
Microsoft.NETCore.App 2.1.19 [C:\Program Files\dotnet\shared\Microsoft.NETCore.App]
Microsoft.NETCore.App 3.1.5 [C:\Program Files\dotnet\shared\Microsoft.NETCore.App]
Microsoft.WindowsDesktop.App 3.1.5 [C:\Program Files\dotnet\shared\Microsoft.WindowsDesktop.App]

To install additional .NET Core runtimes or SDKs:
https://aka.ms/dotnet-download

No source file, test, or entry point is named. Begin by reproducing the ASP.NET Core 3.1 Razor Pages Framework-Dependent deployment described in the issue and inspect why the language and runtimes folders are included; a contribution needs an agreed scope and a verified definition of the desired deployment contents.

Written by the indexing model from the issue text.