This is a problem with software in general. Lazy developers or ignorant bosses stagnate the code to the point where it requires a massive rewrite to bring it up

This is a problem with software in general. Lazy developers or ignorant bosses stagnate the code to the point where it requires a massive rewrite to bring it up to speed. Right now I maintain about 70/30 old code to new code. Most of the old code is because previous developers didn't care at all and were more interested in job stability than code stability. You make a conscious effort to not follow the trends with the framework and thus can only blame yourself for the outcome.