Thanks for that, fg2001. That Windowslatest article definitely convinces me to try the workarounds if/when still necessary in the official release of Win 11....
https://www.windowslatest.com/2021/06/28/youll-be-able-to-bypass-windows-11-tpm-2-0-requirement/
You’ll be able to bypass Windows 11 TPM 2.0 requirement
(1) I've already put the tweak into my Registry. But I'm prepared to do it again during the install (as the article says) in case it is the new Registry that really needs it.
(a) Type "RegEdit" into Search, & click "Run as Administrator".
(b) Copy/paste the following into its Address bar...
HKEY_LOCAL_MACHINE\SYSTEM\Setup
(c) Right-click "Setup" in the left pane, & select "New > Key"...

(d) Type "LabConfig" over what it offers for the name.
(e) Right-click "LabConfig" in the left pane, & select "New > DWORD"...

(f) Type "BypassTPMCheck" over what it offers for a name.
(g) Double-click "BypassTPMCheck in the right pane to edit it.
(h) Type "1" over its default value of "0"...

So, the key finally looks like this...

(i) Repeat from step (e) to add & modify "BypassSecureBootCheck", if necessary.
(2) If that doesn't work, for Method 2, I'll replace the appraiserres.dll that is on a Win 11 USB Installation drive with the one from my Win 10 USB Installation drive. Then I'll try first an upgrade-install with that. If it fails, I'll try a clean install with it. I don't see why I need mess with an .ISO.

Thanks again fg2001. You are a master of information. So far I do not see any of these suggestions will blow up this computer up anyhow.