That's a pretty compelling reason for me. There are some projects (like Chrome, Firefox, or even OpenSceneGraph) that aren't trivial to compile entirely from source. It would be pretty sweet to have a ready-to-build environment with the project and all dependencies one click away.
I wouldn't mind having that as an option though. Like, laptop in for repair, use the online dev environment. Traveling and have to fix a critical bug, hop on the cloud environment.
Web-assembly might help some here; it should be possible for the devs to split this up, depending on the tasks, to client and serverside, maybe depending on your computer specs and on the requirements of the task at hand. That should fix the latency for tasks that need to be instant (code completion) and tasks that can be a few seconds/minutes (compiling/packing). I am aware these are mixed tasks while developing so clever use should be made of what can be done locally and what should be done remotely.
https://coder.com/
I think some people see value in it as a security feature, or ease of development environment setup. There are also collaborative code editing features. You can both get into a file and type in it at the same time. You can get into your project and work on it from any machine, anywhere, even a phone, potentially.
Personally though, I would never take a job where you do most of your coding in the cloud.