What is LoRa TTS? And what is this conclusion based on? I very much agree with the following, which seems to be the opposite of the above, emphasis mine:
I’d consider some home brewed LoRa protocol for the fish tanks, if only to not rely on external network services such as TTN. Also, whatever you choose: LoRa is radio, in a shared radio spectrum, and there are no guarantees that the signals will be received. Be prepared.
Not if most are sensors for which the timestamp at which an uplink is received suffices? (Even for sensors, one should not try to make all transmit at the same time. Of course, one could use a clock to take the measurements at specific times if that’s really important, but then transmission should still be randomized.) Also beware that it’s hard to transmit a downlink right after receiving an uplink; see My application's downlink is always queued for next uplink. So, time synchronisation for LoRaWAN Class A devices is harder than one might think, and subject of a different topic: Time synchronisation of a Node.