Why do you need this sandbox in order to build stuff? What is wrong with building mechanical stuff using actual wood or metal or meccano or lego? What is wrong with building electrical stuff using actual breadboards and wires and components?
Need? No, but it does have one significant advantage, and that is cost vs return. The game is not that expensive, the hardware to run it is not that expensive, and the flexibility within it is pretty significant. Mechanical and electrical projects both require obtaining raw materials per project and tools can be quite expensive. Minecraft also has a significant multiplayer capability which allows collaborative projects on scales a child hobbyist is less likely to have access to.
I would not call it a replacement for other craft projects, but then again I would not consider mechanical/electrical projects a replacement for fiber crafting or vice versa. Different tools, different experience.
I am not sure what misunderstanding of my argument leads you to say that. I'd be against writing in a word processor which limits your vocabulary and sentence structure for no good reason, certainly.
Any project, wood, writing, music, is going to have limitations on it due to the tools or physical laws.
No, but I'd have a problem if one electronic music creation platform (say... Garageband?) massively dominated all other sorts of music composition online or offline.
Ah, the old 'if something is popular and it is not my thing, it is bad!' argument. Why exactly something that draws people in and gets them creating stuff bad? People gravitate twoards the tool and platform that suit them best, so while it is possible if you remove the option they would find other outlets, those outlets have already been rejected by them for not being what they are looking for.
That is remarkably false. Many school field trips and demonstrations and home experiment kits which were routine when I was young are permitted today, at least in the UK.
Not sure where you are paying attention, but I see a vibrant kit marketplace well in excess of what was available 20 or 30 years ago. I envy kids today and the options they have at just a few clicks of a mouse and a little shipping time. I have even been ordering kids projects or reading plans lately because there are so many and they make great little lazy saturday activities. The only place I can think of that is more limited today would be chemistry sets, which were a small market in the first place and their removal impacts a tiny number of (enthusiastic) people.
But on the whole I have seen the market for beginners and experiment kits in pretty much every domain explode, with more variety easier to obtain than ever.