Let's not kid ourselves. Those protections exist for the benefit of corporations, not software developers. If those corporations could have robots write the software and copyright that software and patent it, they absolutely would.
This is also the same reason due to which open source projects often struggle with funding, and why many databases (among other OSS software) are moving towards stricter licenses such as the AGPL.
(There are infrastructure challenges as well, but this thread is about intellectual property.)
If copyright did not exist, you could take it as a google employee and start your own google without going to jail.
Your ability to sue him will be limured, he cant go to jail, he can deckare bancrupsy, and you have to be spesific about what is protected, 'idea' is a vague term that cant be protectedm