I personally take using Cloud9 to the absolute extreme(https://www.trek10.com/blog/i-buy-a-new-work-machine-everyda...), having my Cloud9 env setup scripted and creating a new one every day/project. I don’t really recommend that approach for most folks. Anecdotally, it has paid off well when I left a Mac on a train and I was able to walk in an apple store grab a new one and lost minimal productivity for the day.
However, the flip side of all this is I regularly work with a lot of IT people that have underpowered machines, flaky / poor internet, crazy restrictions on their work machines that cause all sorts of problems with CLI / program installation, etc. I’ve found Cloud9 to be super liberating for those folks particularly with the parity of Cloud9 to AWS Lambda runtimes.
The 95% is still local, but makes remote more ok when ci + jupyter + quick vim isn't enough.
I am a big fan, have been since before Amazon bought it. I’m shocked more vendors don’t have something similar.
I write about AWS products and it's quite nice to get an IDE preinstalled with AWS CLI tools with the push of a button.
For JS it's mostly an okay-ish IDE, not as good as VSCode, but okay.
For things like Rust or Reason it sucks quite much.
I wouldn’t be opposed to a cloud-based primary IDE (as long as it functioned offline), but I don’t think we’re there quite yet.
So it’s not my primary IDE, but it’s a solid backup.