Machine learning APIs have enabled the viability of businesses that were previously not economically feasible. For instance, the ability to record and save meetings on platforms like Zoom has allowed for the creation of a database analyzing discussions at local school boards across the United States. This type of analysis would have previously been too costly to transcribe and analyze manually, but with machine learning language models, it has become economically viable. As an investor, the speaker is now focused on identifying startups that were previously not economically viable, but now thrive due to the availability of machine learning APIs.