I mean in most economic theory ultimately the interests align with those who owns the means of production. In capitalism that is the individual (ideally) and in socialism it’s society (ideally) so not sure what’s wrong with GPs definition. The interest of those who own comes first in either case; that seems self evident.
In capitalism the capital has a life and a mind of its own, independently from the people who own it or serve it as professionals. It wants to grow and accumulate.
Only a mixture of capitalism with socialist policies can be beneficial to man, if you go with absolutes it brings misfortune to most people.