We pass `null` for the class name here:

https://github.com/elastic/elasticsearch/blob/f086dd18ddc705bf84a1ff99d35196ec2498fd52/server/src/main/java/org/elasticsearch/plugins/PluginDescriptor.java#L261

However the class name is mandatory for the transport protocol today:

https://github.com/elastic/elasticsearch/blob/f086dd18ddc705bf84a1ff99d35196ec2498fd52/server/src/main/java/org/elasticsearch/plugins/PluginDescriptor.java#L156

This prevents various APIs from working in a cluster with stable plugins installed.
server/src/main/java/org/elasticsearch/TransportVersions.java
*/
    /**
     * Reference to the earliest compatible transport version to this version of the codebase.
     * This should be the transport version used by the highest minor version of the previous major.
     */
    public static final TransportVersion MINIMUM_COMPATIBLE = V_7_17_0;
    /**
     * Reference to the minimum transport version that can be used with CCS.
     * This should be the transport version used by the previous minor release.
     */
    public static final TransportVersion MINIMUM_CCS_VERSION = V_8_500_061;
    static final NavigableMap<Integer, TransportVersion> VERSION_IDS = getAllVersionIds(TransportVersions.class);
    // 
    static final TransportVersion LATEST_DEFINED;
    static {
        LATEST_DEFINED = VERSION_IDS.lastEntry().getValue();
        // 
        // 
        IDS = null;
    }
    public static NavigableMap<Integer, TransportVersion> getAllVersionIds(Class<?> cls) {
        Map<Integer, String> versionIdFields = new HashMap<>();
        NavigableMap<Integer, TransportVersion> builder = new TreeMap<>();
        Set<String> ignore = Set.of("ZERO", "CURRENT", "MINIMUM_COMPATIBLE", "MINIMUM_CCS_VERSION");
        for (Field declaredField : cls.getFields()) {
            if (declaredField.getType().equals(TransportVersion.class)) {
                String fieldName = declaredField.getName();
                if (ignore.contains(fieldName)) {
                    continue;
                }