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.
{
    if (request.fHelp || request.params.size() > 2)
        throw std::runtime_error(
            "getchaintxstats ( nblocks blockhash )\n"
            "\nCompute statistics about the total number and rate of transactions in the chain.\n"
            "\nArguments:\n"
            "1. nblocks      (numeric, optional) Size of the window in number of blocks (default: one month).\n"
            "2. \"blockhash\"  (string, optional) The hash of the block that ends the window.\n"
            "\nResult:\n"
            "{\n"
            "  \"time\": xxxxx,                         (numeric) The timestamp for the final block in the window in UNIX format.\n"
            "  \"txcount\": xxxxx,                      (numeric) The total number of transactions in the chain up to that point.\n"
            "  \"window_final_block_hash\": \"...\",      (string) The hash of the final block in the window.\n"
            "  \"window_block_count\": xxxxx,           (numeric) Size of the window in number of blocks.\n"
            "  \"window_tx_count\": xxxxx,              (numeric) The number of transactions in the window. Only returned if \"window_block_count\" is > 0.\n"
            "  \"window_interval\": xxxxx,              (numeric) The elapsed time in the window in seconds. Only returned if \"window_block_count\" is > 0.\n"
            "  \"txrate\": x.xx,                        (numeric) The average rate of transactions per second in the window. Only returned if \"window_interval\" is > 0.\n"
            "}\n"
            "\nExamples:\n"