No. The AM4 is an amp modeler, so its whole design is different. It has features like balanced line-level outputs instead of unity gain, and of course the new AM4 Amp block, which includes built-in DynaCabs. To support live amp selection, it introduces Amp Mode on the footswitches—four fully color-customizable channels plus a built-in output boost. It also has a very tasty set of effects blocks but it does not have all of the blocks that are offered on the VP4.
By comparison, the VP4 is specifically designed to add effects to an amp or modeler. It works great with an AM4, but it’s a separate product with a different purpose—not replaced by AM4 in any way.