A lower salary for a developer in low CoL area doesn't indicate that a company values that resource less than another dev in a higher CoL area. It just means that the company has to pay less in order to reward the developer in the low CoL as much as the employer rewards the high CoL dev. The equation looks like this:
Sure, but I still find it interesting to make the following observation:
The CoL modification to the developer's salary has nothing to do with whether the company makes more or less revenue as a result of their work.
My guess is that as companies find good talent increasingly hard to find this problem will resolve itself as the remote workers outside major metropolitan areas get bidded to higher and higher salaries.
salary - CoL/year = reward_dev