Tinybird is “just” a wrapper around Clickhouse. You will definitely need the ghost/traffic-analytics container to add the business logic to deal with ingesting and reading data to/from Tinybird.
The container can be used for multiple sites though. I am running nearly 800 of them through a single one at the moment.
It runs on about 200-300MB memory and 0.5 vCPU cores. So, super lightweight.
See the container as a proxy between the Ghost site and Tinybird. Ghost forwards events from visitors to the traffic-analytics, which then processes it, and stores it in the connected Tinybird workspace.
On the Ghost Admin, the traffic-analytics container is called to request data from Tinybird.
I think for Pikapods the big question is: do you set up one traffic-analytics container for all customers, or does every Ghost customer get their own traffic-analytics container.
The three managed hosting providers (Ghost(Pro), Synaps Media, Magic Pages) that provide this integration so far all use the former approach: a single service for multiple Ghost sites (same for ActivityPub).
Edit: just saw that Midnight also offers Traffic Analytics now, and I assume they also use the same approach.