I think you're confusing value investing with looking at a simple Price/Book ratio. Value investing is much more than that. One method of fundamental analysis involves making a prediction about ~10 years earnings/cash flows and comparing that to the 10 year risk free rate (usually the US 10 year treasury).
The fundamental analysis models don't fall apart with tech companies, it's just much harder to project revenues for a new, volatile, growing business than an old mostly stagnant or slow growing company.
The fundamental analysis models don't fall apart with tech companies, it's just much harder to project revenues for a new, volatile, growing business than an old mostly stagnant or slow growing company.