Thanks! There is a place for web editors (quick edits, new projects) and local editors (working on the same codebase for a longer time).
As warned against we don't want to fall in a rabbit hole of spending all our time on this instead of the other parts of our complete DevOps vision https://about.gitlab.com/2017/10/11/from-dev-to-devops/ (logs, roadmaps, create project on push, binary repository, incremental rollouts, tracing). Therefore we based the web IDE on the awesome VScode. This means that it is a doable effort to maintain it.