This where understanding business matters. AWS makes sense as a business and it benefits mostly from economies of scale which is something unique that a massive company like Amazon can provide the service which few other companies could.
NIH stuff is also rarely externalized outside of the business. Even as open source. Which as the OP pointed out needs proper investment of human capital. Not some side project of a bored engineer or two.
Most innovation happens outside of mega companies by small teams for a good reason. Even the Skunkworks type approach is only useful for certain types of work like Googles X projects. Some B2B SaaS programs roll out of parent organiations but typically they are started by teams who quit the bigger company to solve the problem they had.
The first AWS service was launched over 15 years after Amazon.com started selling books on the Internet. It wasn’t even a separate brand until after Amazon S3, SQS and EC2 were launched.
Close. It was roughly 11 years. I've been using Amazon AWS since early 2007; I believe it launched to the public in the form we know today in early 2006. They started selling books online to the public in mid 1995.
If you go back to the very first AWS services - 2002 - it's closer to being only seven years.
If a different company had dominated the on-demand computing space before Amazon’s peak load issues became too big a problem, they very may as well have gone with that and not made AWS.
Almost nobody needs to write their own chat app. Slack is fine.
The real issue here is a lack of vision at the top. The current CEO needs to step down for the health of the company. He has a clear lack of vision for the company, as evidenced by his statement of "do your divisions look like what they should if we had to start over?" Who says that? Something so vague that is basically grasping at straws and shows a complete lack of strategy. Would Jeff Bezos say something like that? I highly doubt it, because he has complete control over his company and a vision that has worked at micro and macro levels.
You can do things that aren't directly related to your core business and these things should generate value both internally and externally. If you can't do this, eventually, your company will stop growing.