The Iron Law of Bureaucracy implies it's usually the second one though. If the company isn't already dying then the insiders will fight against cuts until it is.
Some companies experience short-term improvements in price as their costs drop, but usually it has a longer-term impact on morale and productivity that takes longer to play out. Additionally, layoffs are typically performed on unhealthy companies (eg. not usually companies like Google and Meta that print cash and have huge margins), and unhealthy companies typically have other secular or structural issues beyond too-many-employees.