While most of the additional functionality the old account system had over the label system were irrelevant, there is one critical functionality that no longer seems to be possible with labels - specifically, the ability to request a list of transactions (TXID + amount) that pay to addresses with a given account/label. As per the release notes for 0.17.0. the _listtransaction_ method was changed as follows;

> The account named parameter has been renamed to dummy. If provided, the dummy parameter must be set to the string *, unless running with the -deprecatedrpc=accounts argument (in which case functionality is unchanged).

_getreceivedbylabel_ and _getreceivedbyaddress_ only returns the balance, while _listreceivedbylabel_ and _listreceivedbyaddress_ do not actually filter; additionally, the former does not list transactions at all, while the latter does not include the amounts per TXID. While you could use _getaddressesbylabel_ to iterate over addresses, there is no corresponding method to get the TXIDs and amounts from this list of addresses. None of these can therefore be used as a direct replacement for this method.

The only way I can see to get anything resembling the old functionality with the API changes is to dump the entire transaction history with _listreceivedbyaddress_, filter the result by label manually, then use _gettransaction_ on each listed TXID. This is both very fiddly and very inefficient, and likely impossible when you go past a certain number of lifetime transactions.

Am I missing something here, or will it really no longer possible be to iterate over transactions received by account/label? If so, this basically means that many applications will no longer be usable with releases starting from Bitcoin Core 0.18.
CWallet* const pwallet = wallet.get();
    if (!EnsureWalletIsAvailable(pwallet, request.fHelp)) {
        return NullUniValue;
    }
    if (request.fHelp || request.params.size() != 0)
        throw std::runtime_error(
            "getwalletinfo\n"
            "Returns an object containing various wallet state info.\n"
            "\nResult:\n"
            "{\n"
            "  \"walletname\": xxxxx,               (string) the wallet name\n"
            "  \"walletversion\": xxxxx,            (numeric) the wallet version\n"
            "  \"balance\": xxxxxxx,                (numeric) the total confirmed balance of the wallet in " + CURRENCY_UNIT + "\n"
            "  \"unconfirmed_balance\": xxx,        (numeric) the total unconfirmed balance of the wallet in " + CURRENCY_UNIT + "\n"
            "  \"immature_balance\": xxxxxx,        (numeric) the total immature balance of the wallet in " + CURRENCY_UNIT + "\n"
            "  \"txcount\": xxxxxxx,                (numeric) the total number of transactions in the wallet\n"
            "  \"keypoololdest\": xxxxxx,           (numeric) the timestamp (seconds since Unix epoch) of the oldest pre-generated key in the key pool\n"
            "  \"keypoolsize\": xxxx,               (numeric) how many new keys are pre-generated (only counts external keys)\n"
            "  \"keypoolsize_hd_internal\": xxxx,   (numeric) how many new keys are pre-generated for internal use (used for change outputs, only appears if the wallet is using this feature, otherwise external keys are used)\n"
            "  \"unlocked_until\": ttt,             (numeric) the timestamp in seconds since epoch (midnight Jan 1 1970 GMT) that the wallet is unlocked for transfers, or 0 if the wallet is locked\n"
            "  \"paytxfee\": x.xxxx,                (numeric) the transaction fee configuration, set in " + CURRENCY_UNIT + "/kB\n"
            "  \"hdseedid\": \"<hash160>\"            (string, optional) the Hash160 of the HD seed (only present when HD is enabled)\n"
            "  \"hdmasterkeyid\": \"<hash160>\"       (string, optional) alias for hdseedid retained for backwards-compatibility. Will be removed in V0.18.\n"
            "  \"private_keys_enabled\": true|false (boolean) false if privatekeys are disabled for this wallet (enforced watch-only wallet)\n"
            "}\n"
            "\nExamples:\n"
            + HelpExampleCli("getwalletinfo", "")
            + HelpExampleRpc("getwalletinfo", "")
        );