Airtable is essentially a database with a user friendly UI and a powerful set of extensions and APIs. You can use Airtable as a spreadsheet, a project management software, or even a full on CRM.
Typically, we see Airtable used most effictively as a good temporary home for new types of structured data, whether it is a new workflow or team coming up to speed or a new dataset that doesn't yet have a home.
Airtable is one of those tools that's really simple to get up and running but then incredibly powerful as you start to use it more and more. Increasingly, it is becoming the 'database' of choice for the no-code community.