https://github.com/bitcoin/bitcoin/blob/d72758c3f6c34cd835f5de3efc230964f3b1ea56/src/torcontrol.cpp#L539

If a user is running Tor proxy outside localhost (perhaps on other host inside LAN or in containerised environment) , the automatic creation of onion services ends up creating an onion service listening to hardcored 127.0.0.1 address on the Tor proxy's host instead of the private address of the bitcoind – effectively running an empty onion service listening the Tor proxy's localhost.
{
    
    if (!connect.empty())
    {
        for (int64_t nLoop = 0;; nLoop++)
        {
            ProcessAddrFetch();
            for (const std::string& strAddr : connect)
            {
                CAddress addr(CService(), NODE_NONE);
                OpenNetworkConnection(addr, false, nullptr, strAddr.c_str(), ConnectionType::MANUAL);
                for (int i = 0; i < 10 && i < nLoop; i++)
                {
                    if (!interruptNet.sleep_for(std::chrono::milliseconds(500)))
                        return;
                }
            }
            if (!interruptNet.sleep_for(std::chrono::milliseconds(500)))
                return;
        }
    }
    
    int64_t nStart = GetTime();
    
    int64_t nNextFeeler = PoissonNextSend(nStart*1000*1000, FEELER_INTERVAL);
    while (!interruptNet)