As someone that have brought katana to dm and played against all weapons with it, I can say confidently say that the current katana in swords can compete with meta sets and even out-play or out-trade popular sets like fist br, cs br, ps br, sigma, tbs. However, the issue is that not only it's easily punishable by aw as usual, but even when you cancel it, you cannot heavy again, which btw, heavy is currently the only thing that lets it stand even with cs along with all other weapons, as even the dash and its charge speed is severely punished by any kind of cancel, dashes and cancels and revenges, only because it's slow, doesn't hit through revenge and takes too long to charge for full damage. It is very satisfying to land it, yes, but more than often, you cannot use it fully outside of crowd control tool, and even then, the utility is very limited.

You can also argue that the lights are usable, but they aren't as versatile as cs's where you are able to input heavy after 1 light without breaking its flow, and often, the travelling of it locks you into place, rather than keeping you mobile unlike cs, landing them also doesn't reward you enough compared to cs light criticals neither does it cancel a target long enough to do light into charge, neither do they make you move forward as much as cs's light. Nerfing heavy while buffing its other aspects does not solve it's core problem which is versatility, and even nerfs its combo potential such as ps light into katana heavy, cs dodges into katana heavy as it will only slowdown the user itself which will be always punished by aws, regardless if legit or macro, and currently, it can mitigate the aw issue but not fully if the aw player in question is skilled with instant aws.

I also did bring katana in td in which consisted of 95% cpdbs and could compete against it, but ultimately could not perform enough when it came to utility or versatility.