Both have an autorouter that does a reasonable job, though many PCB designers scoff at using one for most tasks. Kicad has a nice push-and-shove manual router, which Eagle didn't, though looking back I see they added one a few years back.

Both placement systems just drop all your parts into a grid sorted by reference designator, Eagle doesn't (didn't?) have automatic placement optimization for minimizing ratsnest length, Kicad does have that, plus various plugins to lay out your board like the schematic, auto-place similar groups of components from the schematic hierarchy, etc. Both have trace length matching and can add a meander to reach a given length automatically, Kicad has a built-in impedance calculator.

A critical difference is that Kicad isn't limited to 2-layers, and for small-run high-speed digital work a 4-layer board makes a lot of sense these days and significantly simplifies routing. When all your power and ground signals and decoupling caps just go to a via and then to the internal plane, there's a lot less work to do, and a lot more space in which to do it!