diff --git a/src/java/org/apache/cassandra/config/Config.java b/src/java/org/apache/cassandra/config/Config.java
index 21ef983498d9..c0cad39b5059 100644
--- a/src/java/org/apache/cassandra/config/Config.java
+++ b/src/java/org/apache/cassandra/config/Config.java
@@ -20,6 +20,7 @@
 import java.lang.reflect.Field;
 import java.lang.reflect.Modifier;
 import java.util.ArrayList;
+import java.util.Collections;
 import java.util.List;
 import java.util.Map;
 import java.util.Set;
@@ -292,16 +293,8 @@ public class Config
     public int commitlog_sync_period_in_ms;
     public int commitlog_segment_size_in_mb = 32;
 
-    /**
-     * Indicates the type of compressor to use by default for flushes and sstables.
-     * Can be either "fast" or "adaptive".
-     */
-    public String default_sstable_compression = System.getProperty("cassandra.default_sstable_compression", "fast");
-
     public ParameterizedClass commitlog_compression;
-    public FlushCompression flush_compression = default_sstable_compression.equals("adaptive")
-                                                ? FlushCompression.adaptive
-                                                : FlushCompression.fast;
+    public FlushCompression flush_compression;
     public int commitlog_max_compression_buffers_in_pool = 3;
     public Integer periodic_commitlog_sync_lag_block_in_ms;
     public TransparentDataEncryptionOptions transparent_data_encryption_options = new TransparentDataEncryptionOptions();
diff --git a/src/java/org/apache/cassandra/config/DatabaseDescriptor.java b/src/java/org/apache/cassandra/config/DatabaseDescriptor.java
index 191cf402542a..55f52464b62d 100644
--- a/src/java/org/apache/cassandra/config/DatabaseDescriptor.java
+++ b/src/java/org/apache/cassandra/config/DatabaseDescriptor.java
@@ -2081,7 +2081,9 @@ public static void setCommitLogCompression(ParameterizedClass compressor)
 
     public static Config.FlushCompression getFlushCompression()
     {
-        return conf.flush_compression;
+        return Objects.requireNonNullElseGet(conf.flush_compression, () -> shouldUseAdaptiveCompressionByDefault()
+                                                                           ? Config.FlushCompression.adaptive
+                                                                           : Config.FlushCompression.fast);
     }
 
     public static void setFlushCompression(Config.FlushCompression compression)
@@ -2091,7 +2093,7 @@ public static void setFlushCompression(Config.FlushCompression compression)
 
     public static boolean shouldUseAdaptiveCompressionByDefault()
     {
-        return conf.default_sstable_compression.equals("adaptive");
+        return System.getProperty("cassandra.default_sstable_compression", "fast").equals("adaptive");
     }
 
     /**
diff --git a/src/java/org/apache/cassandra/io/compress/AdaptiveCompressor.java b/src/java/org/apache/cassandra/io/compress/AdaptiveCompressor.java
index 09064f9455b2..b4179745da2f 100644
--- a/src/java/org/apache/cassandra/io/compress/AdaptiveCompressor.java
+++ b/src/java/org/apache/cassandra/io/compress/AdaptiveCompressor.java
@@ -69,11 +69,10 @@
 public class AdaptiveCompressor implements ICompressor
 {
     @VisibleForTesting
-    static final Map<Uses, AdaptiveCompressor.Metrics> metrics = new EnumMap<>(Uses.class)
-    {{
-        put(Uses.FAST_COMPRESSION, new Metrics(Uses.FAST_COMPRESSION));
-        put(Uses.GENERAL, new Metrics(Uses.GENERAL));
-    }};
+    static final Map<Uses, AdaptiveCompressor.Metrics> metrics = new EnumMap<>(Map.of(
+        Uses.FAST_COMPRESSION, new Metrics(Uses.FAST_COMPRESSION),
+        Uses.GENERAL, new Metrics(Uses.GENERAL)
+    ));
 
     protected static final String MIN_COMPRESSION_LEVEL_OPTION_NAME = "min_compression_level";
     protected static final String MAX_COMPRESSION_LEVEL_OPTION_NAME = "max_compression_level";
diff --git a/test/unit/org/apache/cassandra/io/compress/AdaptiveCompressorTest.java b/test/unit/org/apache/cassandra/io/compress/AdaptiveCompressorTest.java
index c43e0bf493aa..b8cf758e933d 100644
--- a/test/unit/org/apache/cassandra/io/compress/AdaptiveCompressorTest.java
+++ b/test/unit/org/apache/cassandra/io/compress/AdaptiveCompressorTest.java
@@ -55,11 +55,11 @@ public void badMaxCompactionQueueLengthParamThrowsExceptionMin()
     @Test
     public void averageRelativeTimeCompressingIsMeasuredProperly() throws IOException, InterruptedException
     {
-        var params = new AdaptiveCompressor.Params(ICompressor.Uses.GENERAL, 10, 10, 0);
+        var params = new AdaptiveCompressor.Params(ICompressor.Uses.GENERAL, 15, 15, 0);
         AdaptiveCompressor c1 = new AdaptiveCompressor(params, () -> 0.0);
         ByteBuffer src = getSrcByteBuffer();
         ByteBuffer dest = getDstByteBuffer(c1);
-        for (int i = 0; i < 10000; i++)
+        for (int i = 0; i < 20000; i++)
         {
             compress(c1, src, dest);
         }