You say that up to 70% of experiments published in peer-reviewed journals cannot be replicated. How many of those 70% become the foundation of scientific theories? If I formulated a theory and supported it with a bunch of experiments I conducted myself, but nobody else can replicate my experiments, how widely accepted do you think my theory would be?
I have no clue how much of the 70% of experiments unreplicable becomes foundations. But that is not what we are arguing. Your point is replicability defines whether or not a discipline can be considered science. My counter point is that many experiments coming out of highly established science labs (including Nobel laureates in physics, chemistry and biology) cannot be replicated. Yet, these are still considered top-notch scientists doing cutting edge science. thus, replicability does not define science, although it is a pivotal part of doing successful science.
Unable to replicate an experiment does not automatically discredit the experiments. As I mentioned before, there are many factors involved. Most common factors are not fraud but unknown/uncontrollable conditions. And in many cases, the original experimenters were actually correct. Others cannot replicate their data because everyone had different conditions.
An interesting example. A few years ago (2013, I think), Nature published a study suggesting that lab animals like mice respond to male vs. female technicians in vastly different and almost opposite ways. Apparently, the testosterone in male technicians makes lab animals highly agitated and they begin to behave in a defensive manner. And their physiological parameters all change accordingly. So if the original experimenter was male, then all other labs with female technicians cannot replicate their original data. I myself have experienced this. With that said, can you dismiss the data collected by male technicians just because they cannot be replicated by others? It is still valid data, just under conditions previously not expected to have any effects on the outcome. Who knows. Those data collected by male technicians and previously thought to be unreplicable may become basis for groundbreaking theories that revolutionize medicine... You cannot simply dismiss it just because it cannot be replicated.
I have been in both shoes. I have attempted to replicate many others' experiments. I would say at least 50% of times, I couldn't replicate the findings. Then a handful times, I actually met with some of the original experimenters. I asked them about those experiments and was able to repeat the experiments after they gave me some tips (most of time it's about very basic conditions). However, most of the time, I had to let the project go because I couldn't replicate them and had no way of contacting the original experimenters. Then many times at meetings and conferences, people come up to me and ask me why they couldn't replicate my findings. I then asked them what they did and corrected a few things. Then they were able to replicate my findings. So based on my experience, replicability is a very complex thing...
Now, let's get back to economics. Many economists are actually classically trained mathematicians and physicists. they know how to do science and how to do it properly. As I said before, economics is such a complex system. Economists need to simplify their models and make assumptions to get their models working. This means that their models become very limited. Yet, this does not mean they are doing pseudo-science. They just need more time to improve and perfect their models.