I think it's the same story as with Snap Circuits for learning electronics, or baking soda + citric acid "chemistry sets". Many parents really wanted their kids to have a STEM career, and so we lowered the bar to the point where STEM-shaped educational activities are accessible to any kid. But because there's no bar to entry, playing with these toys doesn't reliably translate into motivation to really learn electronics, programming, or something like that. That motivation still manifests only in a small percentage of kids. Maybe we're making that percentage go up slightly, but it's a small effect.

FWIW, it's not exactly a new phenomenon. Two decades before Scratch, many schools were using Logo to teach kids programming, probably with similar success rates. Stuff like that is probably good even if it doesn't lead to a STEM "success story". It makes kids actively participate instead of scrolling Tiktok all day.