LinkedIn is replacing functional leadership roles (head of design, head of PM, head of BD, etc.) with product-area leaders who own an area end-to-end, evaluated through 360 reviews gathered across every function they'd need to oversee — not just their home discipline. It's the leadership-layer counterpart to the LinkedIn's Full-Stack Builder Model: just as individual builders are expected to work across research, design, code, and launch, the leaders above them are vetted for the ability to actually deliver across all of those functions rather than defend their original specialty.
Apply: when moving to a full-stack/cross-functional builder structure, don't leave functional leadership roles intact above it — the leadership layer should be restructured and re-evaluated the same way as the builder layer, or it will keep pulling reports back into old functional silos.