The theta/gamma ratio can be thought of as how much you are getting paid per how much risk you are taking.
We find that we are getting paid 1 dollar for every one dollar of risk we take inenvironments. However, in high IV environments, we get paid 6 dollars for every dollar of risk that we take.
This is translated into a higher average daily P/L that we observe in high IV environments.
The/ ratio is another way of thinking about risk/reward in different IV levels.