Quote - "Tandy 1000(A) and was extremely proprietary, much like Macs are now."

Well for the sake of Accurate disclosure Modern Day ( intel)  Macs Are actually Just expensive PC hardware  that have their configurations tightly controlled by Apple.

you can install a Retail Copy of MS windows on second  hard drive or partition on a "Mac" with no Emulation needed
and use it as a PC and run natively AutoDesk programs et all.
this certainly was not the Case with those Awfull Tandy Systems from Radio Shack.

it is the  Mac OS that is under tight EULA and proprietary  but then so is Windows as both MS& Apple have the right to protect their IP.

Cheers

The Mac Hardware is still very proprietary, which is what I was referring to. You can't just plug any old 3rd party hardware into a Mac. The Tandy 1000 was the same.