The problem here is that this is what MSFT wants to tell you officially. There is a big difference in what offiicially is published and what actually can be done. In practice people should just install (IoT) Enterprise or the LTSC versions and avoid home and pro like the plague.
Pedantic point, but there is an x86 version of Windows 11 PE for 21H2 that was publicly released in an ADK. Later versions of the Windows 11 ADK removed the x86 PE though.
Who says this? all IOT editions don't even require the presence of TPM 2.0 or Secureboot out of the box.
Maybe this is a dumb question but regarding Windows 11 IoT Enterprise 26H2, will it be able to upgrade to Windows 11 IoT Enterprise 27H2 if and when that is released or do you need a full reinstall? Edit: This is for the non-LTSC version, thanks.
Why not? It is not a frankenbuild, IoT Enterprise 26H2 non LTSC is a normal edition, it has its own sticky dedicated thread: [DISCUSSION] Windows 11 Build 26x00 (PC) [24/25/26H2 Retail- GE-release]