And what makes governments trustworthy? In the real world democracies tend to do a much better job at being trustworthy then dictatorships. That is due to being controlled by the people by regular votes. The more direct democracy is allowed the more trustworthy the organization becomes. So it is no wonder that capitalist companies, which are in many cases very close to dictatroships, behave as badly as they do and you feel that you need the protection from a more democratic institution. Lets not even pretend that in countries like China or Vietnam judges can not be bought. It is rather simply trust that the other company makes good on its promise as it is long term benefital for both of them to do so.

Which is why the idea of anarcho-syndicalism is to form small scale units producing something and acting as a political organization called syndicates. Those can be joined freely and are organized in a democratic fashion. To get even bigger, those syndicates then send representatives to other syndicates to form federations. Those are made up of all sorts of syndicates working together with free agreement between each other. This also allows for enforcing the agreements between the syndicates as, if one is broken other syndicates will kick your syndicate out of the federation or a lot of them, will just treat them differently as punishment. It depends on the situation obviously.

The key here is to avoid having a proper hierachy, but use free and open deals between the different syndicates, but due to the mass of it, it becomes hard to fully ignore your free contracts. So reputation would absolutly matter.