I use system-wide hotkeys to maximize (fill the screen, not a new fullscreen) windows on macOS by binding it to the standard Window > Zoom command in the menu bar. Window > Zoom item is present in pretty much all native apps on macOS:
Obsidian omits Window > Zoom in the menu bar, so I can’t Zoom (i.e. maximize) obsidian via the keyboard.
Proposed solution
Add the Zoom option to the menu bar under Window.
It’s defined here in the macOS Human Interface Guidelines:
Zoom: Toggles between a predefined size appropriate to the window’s content and the window size people set. Pressing the Option key changes this item to Zoom All.
Current workaround
Option+click the green zoom button in the Obsidian window itself to maximize it.
Related feature requests
Similar requests that seems to have been resolved.
This request is asking for one missing piece, the Zoom command.