Are there more use cases emerging for Airplane that involve moving data between SaaS products or SaaS products and a production data warehouse?

Very occasionally, people will do stuff like that with Airplane. But Airplane is a platform for basically turning code you've written into reusable apps that people can do stuff with. You can definitely write code in Airplane that hits the Salesforce API, and then takes some data and shoves it into Snowflake. 

But there are tools, to your point, that are specific SaaS already, like Zapier or these reverse ETL companies, like HighTouch or Fivetran. They already put data from A to B, and instead of writing code for it, just click three buttons in a UI and it'll do it for you. 

Those companies are better at that than Airplane. Airplane is more generic. We have seen people use Airplane for data pipelines but they're usually highly bespoke data pipelines.