Hmm, why did you build it as a desktop app in 2022? Seems like a no brainer to have this in the cloud so that you can seamlessly process huge files and integrate with various third-party APIs. I've used https://www.gigasheet.com/ for this before (which is cloud-based). And there is also the open source visidata project.
Definitely not a no-brainer. Don't want my CSVs integrating with APIs (or in the cloud at all), and I'm confident the desktop version handles large files better than a cloud solution would, as well as being far more responsive, quick, compact than any web-based solution.
I have zero interest in using business data with some online service that nobody else at my company has vetted. I vastly prefer being able to try and use a desktop application where I can be sure sensitive data is where I have 100% control over it.
I'm absolutely positive that you can make a desktop app a lot more snappy and usable than any browser-based solution. Especially if the point is to edit files on your computer – no way I'd want to upload a 100MB CSV to cloud before even having a sneak peek, but a (good) desktop app would allow a quick sneak peek of even a 10GB CSV.
Not everyone wants their solution hosted in the cloud. I would much rather have this as a desktop app that I can own than yet another SaaS product that I have to rent...