On my 2017 vintage 4-core Xeon machine running workstation 15.5.7, my experience with Windows 11 so far is that the preview releases - which I believe have much relaxed hardware requirements - have installed easily from clean Windows 10 guests.
However now the full release of Windows 11 is available, the situation is quite different, now that the full hardware requirements must be fulfilled. I have tried a clean install onto a new virgin guest, but failed. Secondly I have tried a clean install of a Windows 10 guest with bitlocker encryption and TPM 2.0 support - now the Windows 11 installer complains that "The processor isn't suported for this version of Windows".
In my view this is a VmWare issue that ts virtual processor in Workstation 15.5.x does not emulate the extra machine instructions that Microsoft demands ( cynics view is that MS is pushing for more PC sales to ramp up its sales of Windows 11).
So, point 1 - come on VMWare, step up your game and produce the new machine instruction emulations.
By the way, having initialized my clean W10 guest with Bitlocker encryption, I now have to supply the encryption password every time I want to start the guest.
So, point 2 - VMWare, is that in similar fashion to the seamless integration of TPM 2.0 on a physical machine, Workstation should also make the guest startup free of having to enter encryption password.