FWIW, I didn't read parent post as making an excuse, just describing the reality.
In the corporate world, approximately nobody is rewarded for acting ethically, and as such it's a reasonable assumption that corporations will always trend towards unethical behavior (read: any behavior that pushes costs onto some other entity, while bringing profits to the company), because that can be a competitive advantage.
Acknowledging this is a first step in fixing the problem. We need to incentivize companies to do do the "right thing" - where the "right thing" is something other than simply maximizing profits - because we can't rely on "good people making moral choices" when they are incentivized not to do so.
The only way to achieve a change in behavior in corporations is to change the regulatory framework in which they operate.
In the narrow context of the OP, this doesn't even need to be very heavy handed (unlike say environmental devastation, which is a much bigger challenge). One option would be to pass legislation that makes it harder for megacorps like Cisco to eat smaller companies. Another would be to make layoffs relatively more expensive (require better severance, etc) or to limit them during the M&A phase that Splunk is currently in.
However, if you want tech jobs to have a higher and guaranteed severance, national legislation might be more effective.
After all, many acquisitions and layoffs are at companies that are in dire financial straits, which limits discretionary spending.
There is no reason to over complicate things and require businesses to directly pay, figure out how much cash to always have to be able to pay, hire auditors to make sure they have enough cash, then take them to court when they don’t have enough cash to pay, yadda yadda.
Business sells product or service. Employee sells labor to business. Government takes care of the safety nets.
at every level, the incentive is to maximize the profit margins. If acting ethically doesn't increase the profits, then any personal sacrifice on the part of the decision maker to act ethically is only going to get punished (may be not immediately, but certainly some time in the future).
This is wildly oversimplifying. For example, it theoretically rules out principle-agent problems.
No, you can’t. This is the problem of corporate management. Management will tend to act to maximise profit margins or even the stock price is a bad explanatory model.
Over what time frame?