The sharding_multiversion suite's coverage is strictly greater than sharding_last_stable_mongos_and_mixed_shards. The sharding_last_stable_mongos_and_mixed_shards suite uses mixed versions for the shards, but all the replica set members in a single shard have the same version. The sharding_multiversion suite has different versions within a single shard.

One reason to keep the suite is since sharding_last_stable_mongos_and_mixed_shards chooses binary versions deterministically, it will fail more consistently.