Similar? Yeah.
Similar enough to be considered highway robbery or warrant legal action? No.
I have respect for what Mr. Lyons has done and I think he’s one hell of a graphic designer but there’s some differences here that I think make it too different to warrant saying it’s “stolen”
For starters, the black on black part of the design is nowhere to be found on the official car, that’s like half of the concept design so that alone makes it different enough for me to think that calling it stolen is unjust. The side design is also more different than it looks. His is a straight point while RCR’s comes back and curves almost like the swoosh Nike uses. The front bumper is really the only part that looks like a direct copy imo and even that’s still iffy because that’s a pretty popular design choice for that area, the 3CHI car last year had something different but pretty similar with spikes originating from that area, just higher, above the headlights. Personally this seems like a pretty major overreaction for a spike design in the same place when the main part of the design is pretty different.