From the outside, this doesn't look one sided to me and Motorola (Lenovo) won't want GrapheneOS "locked away".

Motorola partnered with GrapheneOS explicitly because they want the highest security for their enterprise phones (in my opinion), so Motorola demanding GrapheneOS be less secure would be silly for them anyways since they prioritise enterprise (as far as I know).

And in any case, if Motorola caused beef with the GrapheneOS team, I believe in GrapheneOS's morals to ignore stupidity. They probably have a contract anyways that states Motorola have near zero influence over the OS.