Thinking about the past DLC packs, I'm not convinced yet that this year will automatically include a series of modern race cars. I need to wait for one more update before thinking that.
With that said, it would be kinda funny (and probably annoy some fans) if they decided to even include road versions to complement the GT3 cars. Like one update includes a Ford Mustang GT3 for instance and the Mustang Dark Horse or GTD, another has the regular BMW G82 M4 alongside the M4 GT3, Chevrolet Corvette Z06 GT3.R & Corvette C8 Z06, etc.
Though that thought only came in my head because Polyphony decided to add the Ferrari 296 GTB and GT3 at the same time, which is likely just a one-off type of thing since it was the Spec III update.