Performing the following (note the range of 10,000):

`importmulti '[{"desc": "sh(wpkh([aeee1e6a/49h/1h/0h]tpubDC5bVdaveQYxGFztMShFAjU637kKjrs9FD8ne1oHR7z8tLeQJExsaxWRVeSpcCcYMdp5ecf2LQhuVaeYFZ7YEpvWTJr4nDGUJrmuvLuTSsp/1/*))", "keypool": true, "timestamp": "now", "watchonly": true, "internal": true, "range": {"end": 1000}}]' '{"rescan": false}'`

takes many minutes. @achow101 reports a similar import taking 6 minutes on his machine.
{
    WalletBatch batch(*database);
    for (const auto& entry : key_origins) {
        AddKeyOriginWithDB(batch, entry.second.first, entry.second.second);
    }
    for (const CKeyID& id : ordered_pubkeys) {
        auto entry = pubkey_map.find(id);
        if (entry == pubkey_map.end()) {
            continue;
        }
        const CPubKey& pubkey = entry->second;
        CPubKey temp;
        if (!GetPubKey(id, temp) && !AddWatchOnlyWithDB(batch, GetScriptForRawPubKey(pubkey), timestamp)) {
            return false;
        }
        mapKeyMetadata[id].nCreateTime = timestamp;
        
        if (add_keypool) {
            AddKeypoolPubkeyWithDB(pubkey, internal, batch);
            NotifyCanGetAddressesChanged();
        }
    }
    return true;
}
bool CWallet::ImportScriptPubKeys(const std::string& label, const std::set<CScript>& script_pub_keys, const bool have_solving_data, const bool internal, const int64_t timestamp)