As devices become more powerful and more connected, thus increasing the attack surface and the potential losses form them being cracked, the cost-based analysis will start to prioritize security more.

The tools for writing dramatically less brittle code are there, but there's the cost of switching. It needs to become lower than the potential losses. And with the current state of the industry, the losses and lawsuits are surely coming. Remember what it took to make an average e-commerce website become reasonably secure.