We say that we follow the .NET support period for our products, but 7.1 says it is supported until the end of march while .NET 5.0 is only supported until 5/8/2022.
After 5/8, we may not receive security fixes for any issues that come up.
https://dotnet.microsoft.com/en-us/platform/support/policy/dotnet-core

Document Details

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• ID: 0d9a43d3-9571-389c-56ab-7d42a53bf5b1
• Version Independent ID: c138e6a8-fd80-bd64-25ac-24e774e09421
• Content: PowerShell Support Lifecycle - PowerShell
• Content Source: reference/docs-conceptual/install/PowerShell-Support-Lifecycle.md
• Product: powershell
• Technology: powershell-conceptual
• GitHub Login: @sdwheeler
• Microsoft Alias: sewhee