Since they are conceptually more policical techs than commercial.

Description of these techs says othervise.

Cartography

By means of trading and travelling people explored beyond the boundaries of their lands and drew maps of it in order to share and memorize their discoveries.

This has nothing to do with politic, it says trading and traveling and drawing maps.

Diaspora

The extension of trade leads to the permanent establishment of storekeepers and their families in foreign countries, allowing them to exploit the wealth of these countries.

How is this not commercial.

Let's rephrase the descriptions then.
The commit message is quite short, the patch summary gives a more detailed reasoning.

Yeah I'm too short on text sometimes ^^'