Is this due to the fact I have Windows Home?
Windows 10 Home absolutely can run WSL 2 instances. Your current installation is not running a supported build of Windows 10. You will either need to install the current Slow Ring build or wait until Windows 10 version 2004 is released.
Is that the maximum possible build I can have?
Your current installation has not received the proper Windows 10 Insider Preview build, the current Slow Ring build is not 18363.778, but 19041.208, which means enabling WSL 2 is not possible. 18363.778 isn’t even the current Windows 10 version 1909 build.
I'm already part of the Windows Insider program with the Slow setting.
You might have indicated you wanted to receive the proper build, but it has not been installed, you typically must run Windows Update manually for that to happen.
WSL 2 is only available in Windows 10 builds 18917 or higher
Source: Installation Instructions for WSL 2
I downloaded the Windows update installer and ran it manually, all I get now is: Thank you for installing the latest Windows version.
If you are attempting to use Media Creation Tool or the Upgrade Assistant then it has not been updated to install Windows 10 version 2004. The quickest and simplest way to install the proper build is to download the current Slow Ring Windows 10 Insider Preview ISO.
You will need to log into a Microsoft Account, which has become a member of the Windows Insider Preview program. If you do not have a Microsoft Account that satisfies this requirement, you will be unable to install the proper build on your machine.
You should select the current Slow Ring ISO:
- There will be two ISOs, one for 32-bit another for 64-bit download the proper ISO that matches your system.
- Once you have downloaded the file, mount the ISO from within Windows, and run the Setup.exe to migrate your current installation to the current Windows Insider Slow Ring build. You should install all the available updates once you have installed build 19041.