flexRender

function flexRender<TProps>(Comp, props): unknown;

flexRender(cell.column.columnDef.cell, cell.getContext())

Port note: upstream additionally detects class components and
`react.memo`/`react.forward_ref` exotic objects. Both branches are dead in
octane — there are no class components or `forwardRef`, and octane's `memo()`
returns a plain function — so a component is exactly `typeof === 'function'`.
The descriptor `createElement` returns renders at value position; non-component
values (strings, numbers, pre-created descriptors) pass through as-is.