I asked you about the python version because it seems that the reason you can’t run Isaac Sim with the system python is that you don’t have version 3.6.
The computer (where I am running Isaac Sim) has three versions of Python: 2.7, 3.6 and 3.8. By default, the Python interpreter I have is version 3.8.
python python2-futurize python2.7-config python3.6-config python3.8-config
python-config python2-pasteurize python3 python3.6m python3m
python2 python2-qr python3-config python3.6m-config python3m-config
python2-config python2.7 python3.6 python3.8
However, it is only with version 3.6 that I can launch Isaac Sim. With the other two versions, I get the same problem as in your initial question.
It seems to be Isaac Sim is python3.6 dependent. However, the Isaac Sim team (@ltorabi @Sheikh_Dawood @HaiLocLu @Hammad_M) can provide you with more information about that…
Then, you can install python3.6 in your system and use it to set up tkinter, Jupyter notebook, launch Isaac Sim, etc…