[`Setting.versionSetting`](https://github.com/elastic/elasticsearch/blob/0652a5915586abbcdfdfffa91a391740f0147752/server/src/main/java/org/elasticsearch/common/settings/Setting.java#L1275) (only used by index compatibility setting) does not use the `Validator` passed in - its just discarded. Looks like it's been like this since it was introduced by https://github.com/elastic/elasticsearch/pull/83264 in 8.2.0.

Enabling this causes some tests to fail. Enabling this may cause problems for indexes that have a wonky setting already applied.
server/src/main/java/org/elasticsearch/common/settings/Setting.java
return new Setting<>(
            new SimpleKey(key),
            fallbackSetting,
            fallbackSetting::getRaw,
            e -> Enum.valueOf(clazz, e.toUpperCase(Locale.ROOT)),
            validator,
            properties
        );
    }
    /**
     * Creates a setting which specifies a memory size. This can either be
     * specified as an absolute bytes value or as a percentage of the heap
     * memory.
     *
     * @param key the key for the setting
     * @param defaultValue the default value for this setting
     * @param properties properties properties for this setting like scope, filtering...
     * @return the setting object
     */
    public static Setting<ByteSizeValue> memorySizeSetting(String key, ByteSizeValue defaultValue, Property... properties) {
        return memorySizeSetting(key, defaultValue.toString(), properties);
    }
    /**
     * Creates a setting which specifies a memory size. This can either be
     * specified as an absolute bytes value or as a percentage of the heap
     * memory.
     *
     * @param key the key for the setting
     * @param defaultValue a function that supplies the default value for this setting
     * @param properties properties properties for this setting like scope, filtering...