Tombstones are not removed if bloom filter is turned off

Well actually they are deleted, but not always even though they should, because check is done using Index of overlapped tables

When purge evaluator is constructed we are checking overlapping tables using bloom filter, but when it is disabled we are checking against index, but if condition is not properly constructed and we still check bloom filter which is AlwaysPresentFilter and every overlapping sstable is used to get minTimestamp and tombstones, that have their timestamp >= minTimestamp won't be deleted

if (sstable.getBloomFilter() instanceof AlwaysPresentFilter && sstable.getPosition(key, SSTableReader.Operator.EQ, false) != null
    || sstable.getBloomFilter().isPresent(key))
{

Should be something like this

boolean mightBePresentInTable = sstable.getBloomFilter() instanceof AlwaysPresentFilter ? sstable.getPosition(key, SSTableReader.Operator.EQ, false) != null : sstable.getBloomFilter().isPresent(key)

Code pointers in 3.11 https://github.com/apache/cassandra/blob/08363afa5354c00a7ecd62fe273c392a678db28a/src/java/org/apache/cassandra/db/compaction/CompactionController.java#L274 and 4.0 https://github.com/apache/cassandra/blob/11384c3279a66e6c0fb7861e2b188b25e963580f/src/java/org/apache/cassandra/db/compaction/CompactionController.java#L281