While users of Windows 7 and 8 will need a clean install, Windows 11 will still accept Windows 7 and 8 keys. Starting with Windows 8.1 keys in mobile machines are stored in the UEFI.
For those who lack a TPM 2.0 device Windows 10 will be supported through 2025. TPM modules for AM3 machines are known but prices spiked with the Windows 11 announcement.
It is likely that users will need to have an existing Microsoft account on their machines to be able to activate Windows 11 with a digital license.
Microsoft Office is also now using the Microsoft Account to eliminate entering a key with a new install or reset of Windows.