Top ICs work together with ICs that represent their teams, so that they can make informed decisions. They are up to date with technologies (this must be an obligatory requirement), code regularly, so they are much better then managers to make efficient company wide technical decisions, own the architecture of the whole system or large parts, organise and overlook large and expensive engineering initiatives, drive prototypes and research projects. They must me accountable for being up to date, understanding the consequences of their decisions, getting feedback from managers and engineers - not turn into “astronauts” in some years.
I think ICs should go in parallel with engineering management in the reporting chain: the top IC reports to CTO, next level reports to directors, etc. This ensures that IC’s scope of responsibilities is expanding and they have better visibility and power.