No it is designed to be paired to an iPhone. When ever possible it will use the lowest power option for activity on the watch. When your iPhone is nearby: it starts with Bluetooth, then Wi-Fi and finally LTE if that is the only connectivity that is available. Note that LTE is a big power consumer of the available LTE Watch battery.
It can also be used while away from your iPhone but there a restrictions. The watch can't establish new Wi-Fi connections, it can only connect to a Wi-Fi network that the paired iPhone has connected to aka a know Network.
Would you consider it a truly stand alone LTE watch??
Dave
Now considering no I don’t consider it a stand alone device. I also don’t consider it in the same race as a lte Samsung device considering you can use that smart watch if your phone is off. So in theory the Apple Watch is more close to a Bluetooth tethered Watch than a lte device because your iPhone (slave) has to do all the work for it.