This article doesn’t mention it, but there are many companies trying to do this sort of thing and have been running into problems for years. For some of these problems, companies are trying workarounds by genetically engineering algae that has properties that can skip some of these steps. However, this often runs into a different set of problems. It is easy to grow algae, very easy. But it is difficult to grow only the type you wish to grow, and nothing else. Cheap growth ponds only invite contamination from the wind and will lower yields. Also, algae grows so quickly that any problems can cause a collapse in the population if not adressed immediately, unlike other crops like corn. This is manageable with technology, but also adds greatly to cost.
What does the algae do to hurt the population? crawl out of its ponds and murder people?