No, the new Teams 2024 client is not supported on unsupported Windows 10 versions like 21H2, 21H1, 20H2 etc.
Microsoft only supports the new Teams client on the following Windows 10 versions:
Windows 10, version 22H2 (released October 2022)
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Is new teams 2024 supported in unsupported windows 10 versions like 21H2, 21H1, 20H2 etc?
No, the new Teams 2024 client is not supported on unsupported Windows 10 versions like 21H2, 21H1, 20H2 etc.
Microsoft only supports the new Teams client on the following Windows 10 versions:
Windows 10, version 22H2 (released October 2022)