The stress level has gone way up. The company needs instant decisions from information monitored minute to minute. There is not enough time in the day to absorb all of the data coming in all still make all of the right decisions. They don't get to work an 8 hour day if they even want to be a little bit successful. For these larger companies, it is a god damn world market they have to deal with.
A CEO who's getting involved in minute-to-minute decisions is not a good CEO, IMO.
The CEO's role is focused on strategic and logistical issues, not tactical response. It's the front-line staff and, at most, low-level managers who are making immediate decisions. The role of upper managers is to establish the framework in which those lower-level staff make their decisions, and to ensure that everyone in the company has the support and resources to to do their job.
The CEO steers the ship, and "ship" the size of Boeing doesn't turn on a dime. Any competent CEO understands that, so they focus on getting to a chosen destination, not trying to react to every wave.
Yes, there can be some late nights when you're, say, having a video conference with people in China. But any CEO who's failed to equip their staff - and at very least, the rest of their C-team - to make decisions without him for a few hours is a bad CEO.
The owner of the company or the board members, they don't want the job. They'd rather hire someone else to take on the stress and usually your picking among people who don't need the job in the first place.
Officer (e.g. CEO) and director (i.e. board member) are different jobs with different functions.
In smaller companies, sometimes you'll see people do both, but it's a bit of a conflict of interest, and in public corporations, it's often written into the corporate bylaws that a board member can't be an employee of the company.
That being said, it's often the case that a board member of a large company is also the CEO of their own company.
The company is willing to pay what it is worth to them to have someone else do the job. Not a lot of people who can do the job, not a lot of people willing to do the job.
And most CEOs of large companies don't strictly need the job. Most are wealthy before they take the CEO job; most have other income streams. This strengthens their negotiating position.
And because of that negotiating power and the money involved, they also can hire their own lawyer to review their contract and negotiate favourable terms.
For, say, a line worker at Boeing, they can't afford to be without a job, and even if they did hire a lawyer to go over their contract, the company wouldn't be open to negotiating any of the major points of the contract.