It's nuts that no mainstream browser has incorporated basic native table-editing controls by now. (They wasted no time adding JSON pretty-printers—unsurprising, really, given that their main actual concern is propping up the JS–industrial complex and the professional developer class and not real users, which they don't actually give a shit about, contra the Priority of Constituencies.)

There is and has been for a long time a huge opportunity for a "Photopea for CSV (and JSON)" to show up and take off.