I've answered a few of your concerns in a different comment[0].
tl;dr
Autocomplete is just our first product, and it's part of a suite of tools focused on improving developer experience in the terminal. The idea is that you can configure your developer environment in Fig and then we'll sync it across all of your devices.
Fig will always be free for individuals. Teams pay for Fig for collaboration and discovery of internal scripts and for managing dev environment setup and onboarding.
A Linux/Windows version is coming soon. [1] [2]
[0] https://news.ycombinator.com/item?id=31113668.