A new invention in better than an old one if the new invention does what the old one does plus if it resolves another problem using less resources. That's my view...
Pots and pans from the 50s had their bonuses that the ones of today do not... like they could withstand heat and pressure so much, that they never needed to be replaced. Everyone went out and bought them, but then never needed a new one. Thats why today, every pot or pan you get will break apart after enough time.
I think it isn't a question of which are better, in my opinion but the difference behind their creation. Often the inventors of new inventions are just improving the old ones. While this does require creativity, the ability to solve problems with the old, and improving them it is still an improvement on an item that had already been created in the past. On the other hand, improvements require using knowledge that was not always available in the past or the creativity of a younger, and more knowledgeable person considering how the knowledge base of the world has grown and increased since the original creation. On the whole, the adage that "newer is better" can be said to be true.
Lets not go for selling those pans, chances are, we'd run into the same problems that they did in the 50s. Nowadays, companies have learned something... make your product out of something that can fall apart, but still be appreciated by the customer. If you have a coffee machine, that works great, but breaks down every 6 months, and costs 30$, then another, that doesn't break down, and costs 60$, after a 2 year time span, the companies will make double their money on the cheaper coffee maker.