This is related to #14150 and possibly others, but it's actually a separate issue.

For instance, when using the following query:
`bitcoin-cli scantxoutset start '[{"desc":"wpkh(xpubABCDEF/0/*)", "range":100}]'`
I can get a list of UTXOs, but no way to get back the index which derived that particular UTXO. So it's not much better than deriving on the user side and specifying addresses one by one, so that I already have a cache of addresses to match.

Not sure what the solution looks like. One way is to repeat the full descriptor in the utxo. That might get verbose though.
{
    std::string label = value.get_str();
    if (label == "*")
        throw JSONRPCError(RPC_WALLET_INVALID_LABEL_NAME, "Invalid label name");
    return label;
}
static UniValue getnewaddress(const JSONRPCRequest& request)
{
    std::shared_ptr<CWallet> const wallet = GetWalletForJSONRPCRequest(request);
    CWallet* const pwallet = wallet.get();
    if (!EnsureWalletIsAvailable(pwallet, request.fHelp)) {
        return NullUniValue;
    }
    if (request.fHelp || request.params.size() > 2)
        throw std::runtime_error(
            "getnewaddress ( \"label\" \"address_type\" )\n"
            "\nReturns a new Bitcoin address for receiving payments.\n"
            "If 'label' is specified, it is added to the address book \n"
            "so payments received with the address will be associated with 'label'.\n"
            "\nArguments:\n"
            "1. \"label\"          (string, optional) The label name for the address to be linked to. If not provided, the default label \"\" is used. It can also be set to the empty string \"\" to represent the default label. The label does not need to exist, it will be created if there is no label by the given name.\n"
            "2. \"address_type\"   (string, optional) The address type to use. Options are \"legacy\", \"p2sh-segwit\", and \"bech32\". Default is set by -addresstype.\n"
            "\nResult:\n"
            "\"address\"    (string) The new bitcoin address\n"
            "\nExamples:\n"
            + HelpExampleCli("getnewaddress", "")