In late 2017, Trimble announced that SketchUp Make 2017 would be the last downloadable desktop freeware version. Subsequent free iterations migrated entirely to the web browser. This web version lacks support for local offline saving, advanced extensions, and custom plugin integration, which keeps demand for the 2017 desktop package incredibly high. Key Features of SketchUp Make 2017
To be fair, this is a feature article, not a love letter without criticism. SketchUp 2017 lacks modern niceties: