Hello, might that be your problem?
As far as I know - most of the TM1637 clock modules do NOT use I2C. They have CLK and DIO pins. BUT - that does not make them I2C 
I see in your sketch that you include wire.h which you will need for the DS3231.
However, you might be mixing up your digital pins with I2C pins?
If it were me, I would start with a basic arduino, and only one display. Load the necessary library (i.e. TM1637Display.h) and no other libraries and test only that.
Then add wire.h and the ds3231 with it's library. Then the temperature sensor and so on... At some point it will stop working and you will have a better diagnostic.
But to answer the specific question. No, I think these displays are all "standard" digital not I2C.