Open source would definitely be eating the world... though quite a few companies wouldn't be very happy in the process.
That is the end goal, right? Your margin is my opportunity. The problem in the middle is: open source software is considered free-as-in-never-pay-me free.
I have multibillion dollar companies using some of my open source software. They've never paid me anything. They ask for bug fixes and feature improvements that would take me six months (or more) of full time work. They don't offer to pay (or then even balk at the thought), they just keep saying "you should support us for free because it's open source."
Part of the "we won't/can't pay" is due to programmers being very low status people in organizations. Programmers don't have budgets to buy anything because "lol free open source" and "it's just code, do whatever." If programmers could allocate resources towards getting features/fixes they need from external projects, the software world could be more... synergistic.
And if management refuses to allocate a budget for donating back to open source projects (either in developer time or in money) then developers should tell their coworkers that the company they work for is not an open-source friendly company. They're not doing their part to give back to the community of developers who are working so hard in their spare time to make what they do possible. I think the last thing companies want is to build a wall between management and their developer teams like that.
When the default position of management is to fight progress (or hoard private profits enabled by using public goods), playing the role of docile puppies and kittens won't enact change.
Those corporations who do not have good hearts and do not make good choices within their leadership will ultimately lose to those that do. Darwinism in full effect.
EDIT: In fact one of my ideas for a while now is to have a standardized disclosure that corporations could use to publicize to the world how they give back to the open source community (specifically and generally). This public disclosure would be primarily used as a recruiting tool. Eventually if it became big enough, the assumption would be that those who are not disclosing are probably not contributing. Huge implications as a recruiting tool IMO.
And it's not a lot to ask. It's not like you're asking for even $1000's of dollars. Khan Academy I think set the bar when they announced a while back they would allocate $5/mo/developer to allow each developer to donate to open source projects as they saw fit. If a company with a large team of developers can't afford something as simple as that then they have bigger problems.
If you ever do business with corporations, you will get used to the fact, that they will for the moon and expect it for free. It is your task to tell them, what you expect to be paid and stick to it. They won't volunteer any money they don't have to, and will use any excuse that will make it possible (the procurement bonuses depend on money saved). It's up to you to not accept that excuse.
Except, the company endpoint is a low status programmer.
Imagine how quickly the average programmer would get laughed out of the room if they went to their manager and asked for $100,000 to pay an external contractor to implement a feature they need. Oh, also the feature will be open source and other companies will be able to use it after it's written too.
The world doesn't operate on that level yet outside of maybe seven companies in the world.