Today, the hybrid matching logic will only be exercised by queries with a $lookup or $group in the main build. In the all feature flags build, the hybrid matching logic will not be used at all, since it is disabled when the SBE plan cache is used.

After some discussion with others, we've agreed to add a new build variant that runs with SBE full enabled, and the plan cache disabled, so that the hybrid matching logic is exercised more thoroughly.

In addition, we should write a JS test which exercises interesting match expression behavior before an SBE-compatible $group or $lookup.