yeah meanwhile iron is literally nescessary to make your blood transport oxygen. Mo and Be (and their alloys) just have similar strength to weight ratios, but they aren’t exactly practical drop in replacements. So yeah, I haven’t found anything better than steel, there’s just materials that are better in one or two aspects, but nothing with the versatility of steel. To be fair, we have thousands of years of research into steel, perhaps we can still find something better. Idk, maybe some high entropy alloy.