This issue has persisted since Forza Motorsport 3, but was only amplified in Motorsport 5 for no particular reason. The Enkei NT03+M wheels in Forza are very inaccurate. Unnecessarily, their highest LOD model seems to be modeled for the smallest possible wheel size, given the massive centre part of the wheel. Lower LOD models are scaled better, but are still low quality.
Here is how these wheels look in both Forza Motorsport and Horizon 5. Despite a different texture in FM, the model is still the same. Only Horizon 5 allows me to access the lowest LOD model through a glitchure.
Here is how these wheels impact a car’s visuals at the size of 18". Additional Horizon 5 footage showing low LOD wheels with less inaccurate dimensions
Real life footage of Enkei NT03+M for comparison
Additionally, Enkei NT03+M in FM have some Custom Paint texture issues: Zinc and Iridescent colours show Colour Bleed, where the default colour remains visible