That's an interesting question Christoph.
Many of our clients don't actually know their company goals, and even if they do know their goals the PMO may be overstepping their bounds if they try to impose alignment.
I strongly agree with your point about making portfolio and staffing very public. It's pretty common that the organization doesn't know their own resource capacity or utilization.
The common form of Matrix we see makes the individual employee accountable for the reconciliation of supply / demand imbalances. Simply put: the work piles on in an uncontrolled fashion that may actually be correlated to the worker's usefulness and value, and the individual knowledge worker is the only person on the planet who can see the entirety of the demand. Thus, they have to figure out what to work on, when. Thus, they decide what NOT to work on every day.
If Management doesn't like the decisions being made, it's Management's fault since they're the ones who decided not to manage. Back in the 1990's when "Empowerment" was introduced, Management abdicated their duty to manage.
So if a company wants to align the projects with their goals, they should start by ensuring that the resource capacity is directed properly.