I can't imagine people enjoying web based IDEs. I used to work for a company that has everything made internally, including IDE -- they used the same method OP described -- using VSCode on web. The experience is horrible.
I guess maybe it was fancy back in mid 2010s, but my experience was a couple of years ago.
From the article: “ Cider was a light client that opened much faster than traditional IDEs. All the magic happened on a backend that indexes the entire codebase, so that all the data was ready whenever someone opened the webpage. ”
Sounds like all other editors were slow compared to Cider.