In the clustered_collection.js multiversion test we assert that 5.0 and last-continuous (5.2) nodes can't start up with clustered collections present, but the error is not helpful:

[js_test:clustered_collection] d20271| 2022-02-22T21:10:20.007+00:00 E  CONTROL  20557   [initandlisten] "DBException in initAndListen, terminating","attr":{"error":"BadValue: 'clusteredIndex' has to be a boolean."}

This is intended, but we must verify that existing clustered collections are not affected if we downgrade the FCV version of an already running cluster with clustered collections present.