Yea, this is where things get really stupid. The contribution of shareholders is very close to nil - the CEO may be the most impactful employee (though I think they're honestly not nearly as important as modern society says, being a replaceable cog themselves) but they are not worth the equivalent of 20 or 5000 employees.
How about we compare to engineering wages in other companies with similar profits? Pretty much any other large engineering company. Or how about the oil industry? where profits are higher, the risk to life way higher, yet engineers make 80-100k?
What you have in these companies are single large shareholders vs institutional or family shareholders. That's what you're ultimately uncomfortable with. One person having so much net work.
Why? Why not vs. CEO compensation? Is there some rule that CEOs and shareholders must make absurdly more money than workers, or society will collapse? CEO salaries are routinely defended with "that's what they're worth" - why does this not apply to the lowly worker?