The issue seems to stem from the vault i’m using.
I created a new vault and it saved the zoom value.
The Vault with the problem was created in Obsidian 0.12.19.
Solved the issue by creating a new vault and copying the data, so obsidian would create a new settings file/folder
Seems to be that Obsidian 1.0.3 has problems interpreting the files from the hidden .obsidian folder in the vault if that was created by an older version, the files in mine were created by Version 0.12.19