You may have noticed that SketchUp is not anymore “3D for Everyone” since 21st May 2013 (since then just “the easiest way to draw in 3D” or “where great ideas get to work”).
For me it didn’t seem like a “switch” from one product to the other but two separate developments and a decision. Before that, SketchUp for Web (or my.sketchup) was an additional product for education and mobile and like a demo app “try it before downloading”. Independent from that, they had already tried various ways to fight piracy and unlicensed usage of SketchUp Make (first non-Pro SketchUp was “portable” and worked without preferences, then it got a forced trial of Pro and would degrade to free, then it got a license file for agreement to non-commercial use and would degrade to an expired disfunctional Pro when run as portable app without preferences and license file). The switch only occured with a clear discontinuation of one product, SketchUp Make.
I see it similar to Firefox: It used to be the browser whose identity was defined by addons. When browsers simplified and reduced their UIs, people felt less need for addons (and that people nowadays let themselves be consumed by platform economy, drawn to the platform who advertizes louder).
What is SketchUp Make/Free’s identity when it is not extensions anymore? Is the web version easy to use for real stuff, without extensions? SketchUp will remain a purely professional app and interest by the general public will diminish.
When using software for spare time projects, it is for me ok playing an old game and knowing it was a nice pastime when it is over. But when investing spare time and effort for building something long-lasting, I would take into consideration whether the software has stalled development years ago (same criteria as a commercial company would have). Even if the discontinued software still works fine now. Afterall I want to be able to open the files and further develop the project in 5, 10 years whenever I enjoy to!