Devil's advocate: IANAL but my understanding is that the kind of safe harbors that exist in other areas of IP law, e.g. that network providers are not responsible for copyright violations, either do not apply to export controls or have not been subject to sufficient legal review to establish a precedent that would protect Google from export control liability from software that is hosted by customers on their infrastructure where the customer has not undertaken the necessary measures to implement the export controls required by law.

If you think the law is unjust, then target the law, don't target the companies which err on the side of legal caution. After all, certainly we'd prefer for companies to err on the side of regulators in many other cases...