Those trade networks for tin really weren't necessary. Somehow people didn't realize there is tin in both Anatolia and in mainland Greece. The later Phoenicians established trade ports as far as Cadiz in Spain where they traded for tin from Britain. This was an unnecessarily long way for tin to travel. But yes, the skyrocketing bronze prices might have bankrupted Egypt as it armed and armored its soldiers to prepare for the expected attack of the Sea Peoples. Egypt managed to defeat them, but it was never the same again.