The author of Zod had an insightful comment on FOSS and monetization https://twitter.com/colinhacks/status/1422222156340072456

> whether an OSS project lends itself to monetization is a really interesting and subtle question. rule of thumb, be at least two of these: big, boring (roughly correlates with "infrastructural" as @patio11 puts it), and lacking obvious substitutes

The monetization strategy is only a part of the viability story.