Looking at recently merged pull requests that were less than 120 days old, apache/superset had 89 unique authors, which is very high, as the following shows:
https://oss.gitsense.com/insights/github?q=pull-age%3A%3C%3D...
Metabase had 37 authors, which is also quite high for an opensource project, which the following shows:
https://oss.gitsense.com/insights/github?q=pull-age%3A%3C%3D...
And redash has 11, but most of the contributions were more than 28 days ago, and is significantly less active than metabase and superset as the following shows:
https://oss.gitsense.com/insights/github?q=pull-age%3A%3C%3D...
I was actually quite surprised by superset, as I never heard of them before, but they are backed by serious investment (https://preset.io/about/), which clearly shows in how active their repository is.