diff --git a/pom.xml b/pom.xml
index 53644d4b..59a36c2d 100644
--- a/pom.xml
+++ b/pom.xml
@@ -245,6 +245,11 @@
                         <breakBuildOnBinaryIncompatibleModifications>true</breakBuildOnBinaryIncompatibleModifications>
                         <breakBuildOnSourceIncompatibleModifications>true</breakBuildOnSourceIncompatibleModifications>
                         <excludes>
+                            <!-- public -->
+                            <!-- removed -->
+                            <exclude>
+                                com.fasterxml.jackson.module.kotlin.MissingKotlinParameterException#MissingKotlinParameterException(kotlin.reflect.KParameter,java.io.Closeable,java.lang.String)
+                            </exclude>
                         </excludes>
                     </parameter>
                 </configuration>
diff --git a/release-notes/CREDITS-2.x b/release-notes/CREDITS-2.x
index 6a7d5934..231186cd 100644
--- a/release-notes/CREDITS-2.x
+++ b/release-notes/CREDITS-2.x
@@ -18,6 +18,7 @@ Contributors:
 # 2.20.0 (not yet released)
 
 WrongWrong (@k163377)
+* #969: Cleanup of deprecated contents
 * #967: Update settings for 2.20
 
 # 2.19.1 (not yet released)
diff --git a/release-notes/VERSION-2.x b/release-notes/VERSION-2.x
index 78231626..c23ff038 100644
--- a/release-notes/VERSION-2.x
+++ b/release-notes/VERSION-2.x
@@ -18,6 +18,7 @@ Co-maintainers:
 
 2.20.0 (not yet released)
 
+#969: Deprecated content has been cleaned up with the version upgrade.
 #967: Kotlin has been upgraded to 2.0.21.
 
 2.19.1 (not yet released)
diff --git a/src/main/kotlin/com/fasterxml/jackson/module/kotlin/Exceptions.kt b/src/main/kotlin/com/fasterxml/jackson/module/kotlin/Exceptions.kt
index 120ad0f0..3e9981c6 100644
--- a/src/main/kotlin/com/fasterxml/jackson/module/kotlin/Exceptions.kt
+++ b/src/main/kotlin/com/fasterxml/jackson/module/kotlin/Exceptions.kt
@@ -3,7 +3,6 @@ package com.fasterxml.jackson.module.kotlin
 import com.fasterxml.jackson.core.JsonParser
 import com.fasterxml.jackson.databind.JsonMappingException
 import com.fasterxml.jackson.databind.exc.InvalidNullException
-import java.io.Closeable
 import kotlin.reflect.KParameter
 
 /**
@@ -31,15 +30,4 @@ class MissingKotlinParameterException(
     val parameter: KParameter,
     processor: JsonParser? = null,
     msg: String
-) : InvalidNullException(processor, msg, null) {
-    @Deprecated(
-        "Use main constructor, ",
-        ReplaceWith("MissingKotlinParameterException(KParameter, JsonParser?, String)"),
-        DeprecationLevel.ERROR,
-    )
-    constructor(
-            parameter: KParameter,
-            processor: Closeable? = null,
-            msg: String
-    ) : this(parameter, processor as JsonParser, msg)
-}
+) : InvalidNullException(processor, msg, null)
diff --git a/src/main/kotlin/com/fasterxml/jackson/module/kotlin/KotlinFeature.kt b/src/main/kotlin/com/fasterxml/jackson/module/kotlin/KotlinFeature.kt
index e7e12d5b..1e9a62a9 100644
--- a/src/main/kotlin/com/fasterxml/jackson/module/kotlin/KotlinFeature.kt
+++ b/src/main/kotlin/com/fasterxml/jackson/module/kotlin/KotlinFeature.kt
@@ -43,7 +43,7 @@ enum class KotlinFeature(internal val enabledByDefault: Boolean) {
      * Enabling it protects against this but has significant performance impact.
      */
     @Deprecated(
-        level = DeprecationLevel.WARNING,
+        level = DeprecationLevel.ERROR,
         message = "This option will be migrated to the new backend in 2.21.",
         replaceWith = ReplaceWith("NewStrictNullChecks")
     )
diff --git a/src/main/kotlin/com/fasterxml/jackson/module/kotlin/KotlinModule.kt b/src/main/kotlin/com/fasterxml/jackson/module/kotlin/KotlinModule.kt
index f09b1707..d14e0293 100644
--- a/src/main/kotlin/com/fasterxml/jackson/module/kotlin/KotlinModule.kt
+++ b/src/main/kotlin/com/fasterxml/jackson/module/kotlin/KotlinModule.kt
@@ -43,6 +43,7 @@ class KotlinModule private constructor(
     val nullToEmptyMap: Boolean = NullToEmptyMap.enabledByDefault,
     val nullIsSameAsDefault: Boolean = NullIsSameAsDefault.enabledByDefault,
     val singletonSupport: Boolean = SingletonSupport.enabledByDefault,
+    @Suppress("DEPRECATION_ERROR")
     strictNullChecks: Boolean = StrictNullChecks.enabledByDefault,
     val kotlinPropertyNameAsImplicitName: Boolean = KotlinPropertyNameAsImplicitName.enabledByDefault,
     val useJavaDurationConversion: Boolean = UseJavaDurationConversion.enabledByDefault,
@@ -59,7 +60,7 @@ class KotlinModule private constructor(
      * Now that 2 is complete, deprecation is in progress for 3.
      */
     @Deprecated(
-        level = DeprecationLevel.WARNING,
+        level = DeprecationLevel.ERROR,
         message = "This property is scheduled to be removed in 2.21 or later" +
                 " in order to unify the use of KotlinFeature.",
         replaceWith = ReplaceWith("singletonSupport")
@@ -96,6 +97,7 @@ class KotlinModule private constructor(
         builder.isEnabled(NullToEmptyMap),
         builder.isEnabled(NullIsSameAsDefault),
         builder.isEnabled(SingletonSupport),
+        @Suppress("DEPRECATION_ERROR")
         builder.isEnabled(StrictNullChecks),
         builder.isEnabled(KotlinPropertyNameAsImplicitName),
         builder.isEnabled(UseJavaDurationConversion),