This more recently happened to IBM (as a computer manufacturer). If your platform is not accessible to hobbyists, the next generation will not be familiar with it, and when they go get a job, it probably won't be with the technology they don't know. Then, assuming there is a credible alternative, the inaccessible technology will die out in a generation, as we've seen with IBM mainframes.

Yes, many companies even start with hobbyist tools. IBM proves that going all B2B is not a good idea.

The other end of the problem is Apple which is a consumer company, but they prohibit companies to use their hardware for building new things.

Both approaches suck for consumers and/or startups, but Apple's approach at least works for them from a business perspective.