Wait so where did the Matrix come from if not Primus? Did Solus make it?
The Matrix definitely came from Primus, he just didn't purposefully make it. He's dead, so he can't purposefully do anything :P
Think of it this way; a holy man known for resurrecting the dead perishes himself, and gets buried under the shade of his favorite tree. Some time passes, and starting from the next harvest, the tree gives fruit that can heal wounds and many illnesses, fertilized by the holy ground it now dwells and thrives in. The holy man didn't intend for the tree to produce healing fruit - he can't intend much of anything, being dead - and yet it still sprouts. It may not resurrect the dead, and it may not last forever, but the healing fruit is still there the next harvest.
Primus was a good god, and the hope he had for the universe still comes through what Cybertron produces, even if he's no longer there to do anything about it.











