“We’re pleased to announce that as of today Arduino IDE 2.0 has moved to stable and is available for download.”
The new IDE is built on Eclipse Theia, the same architecture as VS Code, with a TypeScript front end and a Go back end. It took from spring 2021 to get out of beta. A new Remote Sketchbook stores your code in Arduino Cloud. The free tool now has a funnel to the paid one.