"Trustless" is a terrible meme, as the term is misleading and the implementation of the concept is impossible. The truth is:

There is no cloud, just other people's computers.

Smart contracts can make trust relationships explicit.

By using a blockchain system, you entrust a network - which you may have no control over - with application state. If you rely on such a network, you indirectly also rely on the network infrastructure and operators' social and economic incentives.