https://en.wikipedia.org/wiki/Criticisms_of_the_labour_theor...https://thedispatch.com/newsletter/gfile/everything-wrong-wi... (free subscription required to read the full article, but you can use a throwaway email address)
In short, it's too simple to work in an economy as complex as ours, it completely ignores the impact of demand, and it assumes all workers are equally productive.