Tit for tat reciprocity is the basis of most modern trade relations.

To give a related, similar, but not exactly the same example, in order to demonstrate this idea of reciprocal trade relations:

If country A puts a tariff on country B, then it is almost guaranteed that Country B will put the same exact tariff on country A.

This example is used to demonstrate the principle of trade related relations.

This is how trade relations have worked for a very long time.

And actions regarding international, hundred billion dollar companies, are going to be related to this idea of trade and reciprocal trade relations.

What tariff? What trade? What does this action have to do with either?

The person you responded quite clearly stated it was an approximation to other trade situations. Your response reads as a little disingenuous given the text above, but if it was genuine the "trade" is the provision of services for the exchange of money with Chinese-owned apps. Providing software services like any other service, and indeed like physical goods, is trade all the same.

Tariff may not have been a perfectly analogous choice, but prohibition can also be seen economically as an infinite tariff. China has put bans (infinite tariffs) on a great many US and other foreign companies' services and this is some, comparatively small, reciprocation.