Sort of, but not really. There’s basically two problems with the katana. The metallurgy and the design. You can’t really fix either one without making it no longer a katana.
The design issue is just that the grip and use of the blade is awkward in comparison to most swords. (Not just European ones.) Now, Kendo is (and other Japanese forms are) built around minimizing the design’s weaknesses, but there’s only so much it can do.
You could theoretically fix the design in any number of ways, but in the process it would stop being a katana, and become another variant of the sword.
The same thing applies to the metallurgy. The folding technique was required to deal with the pig iron that Japan had access to. For their resources, and the technology they had, it was the best way they could make a functional weapon. But it doesn’t actually improve the weapon in any way when you’re dealing with modern, high quality steel.
Something I hadn’t learned until recently is, there’s actually some criticism of the WWII era Imperial swords, claiming that, because they were made from other forms of steel, and because they were (in some cases) machined, they’re not true katanas. They fit the design, but, again, some people contend they’re no longer really katanas, just swords designed to look like them.
You can mill a high quality steel blade with carbon nano tube reinforcements, and tempered in liquid nitrogen, but it’s no longer a katana.
The most important thing to understand about the katana is, it’s not just a sword. It’s a very important icon to the Japanese. It’s a part of their cultural identity. So there’s an identity attributed to them that goes way beyond the physical weapon. Much like a bald eagle is incredibly evocative to Americans.
As a weapon, the sword itself is just another (now fairly outdated) chunk of steel. The implication of what it means is where you get the myth of The Katana. The singular perfect sword that all other katanas are pale reflections of.