Dotnet Workload installation failed: Workload ID android/maui/ios isn't supported on this platform

Question

Background: I try to get the Uno framework installed on a Windows PC, but the "uno-check" application fails on installing dotnet workloads:

fix failed - Workload Install failed: `dotnet workload install --from-rollback-file "C:\TEMP\uno-check-be5e2d2d\workload.json" android ios maccatalyst macos maui --source "https://api.nuget.org/v3/index.json"

Problem when I manually execute this workload install, I get the marginally more descriptive error Workload installation failed: *Workload ID android isn't supported on this platform*.

I am running Windows 22H2 19045.4651, VS 17.11.1, and Dotnet 8.0.3 (apparently with maui-windows workload installed):

> dotnet --info
.NET SDK:
 Version:           8.0.303
 Commit:            29ab8e3268
 Workload version:  8.0.300-manifests.56cd0383
 MSBuild version:   17.10.4+10fbfbf2e

Runtime Environment:
 OS Name:     Windows
 OS Version:  10.0.19045
 OS Platform: Windows
 RID:         win-x86
 Base Path:   C:\Program Files (x86)\dotnet\sdk\8.0.303\

.NET workloads installed:
 [maui-windows]
   Installation Source: VS 17.11.35219.272
   Manifest Version:    8.0.72/8.0.100
   Manifest Path:       C:\Program Files (x86)\dotnet\sdk-manifests\8.0.100\microsoft.net.sdk.maui\8.0.72\WorkloadManifest.json
   Install Type:        FileBased


Host:
  Version:      8.0.8
  Architecture: x86
  Commit:       08338fcaa5

.NET SDKs installed:
  8.0.303 [C:\Program Files (x86)\dotnet\sdk]

.NET runtimes installed:
  Microsoft.AspNetCore.App 5.0.1 [C:\Program Files (x86)\dotnet\shared\Microsoft.AspNetCore.App]
  Microsoft.AspNetCore.App 6.0.33 [C:\Program Files (x86)\dotnet\shared\Microsoft.AspNetCore.App]
  Microsoft.AspNetCore.App 8.0.7 [C:\Program Files (x86)\dotnet\shared\Microsoft.AspNetCore.App]
  Microsoft.AspNetCore.App 8.0.8 [C:\Program Files (x86)\dotnet\shared\Microsoft.AspNetCore.App]
  Microsoft.NETCore.App 5.0.1 [C:\Program Files (x86)\dotnet\shared\Microsoft.NETCore.App]
  Microsoft.NETCore.App 6.0.29 [C:\Program Files (x86)\dotnet\shared\Microsoft.NETCore.App]
  Microsoft.NETCore.App 6.0.33 [C:\Program Files (x86)\dotnet\shared\Microsoft.NETCore.App]
  Microsoft.NETCore.App 7.0.20 [C:\Program Files (x86)\dotnet\shared\Microsoft.NETCore.App]
  Microsoft.NETCore.App 8.0.7 [C:\Program Files (x86)\dotnet\shared\Microsoft.NETCore.App]
  Microsoft.NETCore.App 8.0.8 [C:\Program Files (x86)\dotnet\shared\Microsoft.NETCore.App]
  Microsoft.WindowsDesktop.App 6.0.29 [C:\Program Files (x86)\dotnet\shared\Microsoft.WindowsDesktop.App]
  Microsoft.WindowsDesktop.App 6.0.33 [C:\Program Files (x86)\dotnet\shared\Microsoft.WindowsDesktop.App]
  Microsoft.WindowsDesktop.App 7.0.20 [C:\Program Files (x86)\dotnet\shared\Microsoft.WindowsDesktop.App]
  Microsoft.WindowsDesktop.App 8.0.7 [C:\Program Files (x86)\dotnet\shared\Microsoft.WindowsDesktop.App]
  Microsoft.WindowsDesktop.App 8.0.8 [C:\Program Files (x86)\dotnet\shared\Microsoft.WindowsDesktop.App]

Other architectures found:
  x64   [C:\Program Files\dotnet]
    registered at [HKLM\SOFTWARE\dotnet\Setup\InstalledVersions\x64\InstallLocation]

Environment variables:
  Not set

global.json file:
  Not found

• I tried splitting the install up (running as admin): dotnet workload install android, but the same happens, for each of the workloads

• Removed any except for "https://api.nuget.org/v3/index.json" from the Nuget URL.

• Updated Visual Studio, made sure that .Net Multi-platform App UI development and Mobile development with C++ is installed as well

• Removed other Visual Studio installation

• FUll .Net uninstall and reinstall of just 8 + full Visual Study uninstall+reinstall

UPDATE: No solution but more clues to the issue.

The problem seems to be that the Workloads are not recognized; In fact, the list of installable Workloads is very empty, and has a lot less entries than I have seen in examples:

C:\...>dotnet workload search

Workload ID       Description
--------------------------------------------------------------------
macos             .NET SDK Workload for building macOS applications.
maui-tizen        .NET MAUI SDK for Tizen
maui-windows      .NET MAUI SDK for Windows

Even though the manifests (that, if I understand it correctly, let the system know which workloads can be installed) do seem to exist

C:\...>dotnet workload update --ignore-failed-sources

Updated advertising manifest microsoft.net.workload.emscripten.net7.
Updated advertising manifest microsoft.net.sdk.aspire.
Updated advertising manifest microsoft.net.workload.emscripten.current.
Updated advertising manifest microsoft.net.sdk.maccatalyst.
Updated advertising manifest microsoft.net.workload.mono.toolchain.net6.
Updated advertising manifest microsoft.net.workload.mono.toolchain.net7.
Updated advertising manifest microsoft.net.workload.mono.toolchain.current.
Updated advertising manifest microsoft.net.workload.emscripten.net6.
Updated advertising manifest microsoft.net.sdk.android.
Updated advertising manifest microsoft.net.sdk.macos.
Updated advertising manifest microsoft.net.sdk.tvos.
Updated advertising manifest microsoft.net.sdk.ios.
Updated advertising manifest microsoft.net.sdk.maui.