TinkerCAD has a low enough learning curve that it is successfully used to teach elementary school students how to model. I disagree with your “but it’s a complex program, so it can’t be easy to pick up.”
Something being inaccessible to the masses shouldn’t be a badge of pride. Make the basics relatively easy to learn, and design the complex elements in a way that builds on the knowledge used for whatever was needed to get to that point. If we want to increase usership of FOSS products, we need the barrier to entry to be at least on par with the commercial products, if not lower. In fact, dedicating a few dev cycles towards new user onboarding to walk people through sketches, extruding, etc. to make it as accessible as possible would make such a difference.
Oh, yeah, I understood sketches being the starting point, I just lived on the struggle bus any time I tried to sketch anything. The interface is close enough to vector drawing, that it constantly felt like I knew what I was doing, except everything I did threw an error 😅 or the things that in vector drawing would be a simple ‘click on an anchor and drag’, are multi-step processes involving a spreadsheet here.
I know a lot of it is a matter of practice, and I’m sure there are also growing pains for the software. I’m genuinely excited by the changes they’ve made to modifying sketches, and the little explanations at the bottom of the screen, I hope they are able to keep the momentum going.