Install information is incorrect for dotnet on Ubuntu 20.04LTS with WSL2

[SquidPony]

Information is incomplete (at least on WSL2 and Ubuntu 20.04LTS)

sudo apt-get update; \ sudo apt-get install -y apt-transport-https && \ sudo apt-get update && \ sudo apt-get install -y dotnet-sdk-3.1

gives the error

Some packages could not be installed. This may mean that you have
requested an impossible situation or if you are using the unstable
distribution that some required packages have not yet been created
or been moved out of Incoming.
The following information may help to resolve the situation:

The following packages have unmet dependencies:
 dotnet-sdk-3.1 : Depends: dotnet-runtime-3.1 (>= 3.1.1) but it is not going to be installed
                  Depends: aspnetcore-runtime-3.1 (>= 3.1.1) but it is not going to be installed
E: Unable to correct problems, you have held broken packages.

This is with a new WSL2 and Windows Store provided Ubuntu 20.04LTS setup.

Following the troubleshooting advice from 1822 and 3328 led me to believe that this is a long-standing issue with the way the Ubuntu system is set up, causing the instructions in the referenced page to be incorrect in some cases.

Going down a rabbit hole of many many issues similar to this, I found the following which resolved this issue: 4360

Image of above comment for ease of discussion:

The docs should be updated to indicate that the above might be needed.

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Document Details

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• ID: 80707602-f283-e796-d3b8-3287fbc011dc
• Version Independent ID: 1d732b15-9e64-633a-000c-ad96d9d3818a
• Content: Install .NET Core on Ubuntu - .NET Core
• Content Source: docs/core/install/linux-ubuntu.md
• Product: dotnet-core
• GitHub Login: @adegeo
• Microsoft Alias: adegeo