Csvkit is great, and I use it a lot. The target users for CSV Explorer though are mostly non-engineers ie. people who don't use the command line or code.
Kibana has quite a few rough edges but it takes non-technical users very far in terms of data exploration. Local setup also alleviates privacy concerns.
The bummer is import/export: 'Upload CSV' feature has been almost introduced in 5.0 release but removed in the end [1], and CSV export has been asked for many times [2] but is still not there. So a user-friendly fork might be a worthy business idea.
[1]: https://github.com/elastic/kibana/pull/8497 [2]: https://github.com/elastic/kibana/issues/1992