Hi
@rbkyorem,
I hope you're doing well. This change is intentional, the default 3D PCB creation in Fusion360 converts the copper into actual geometry, which can be super useful if you have access to a milling machine. If you want the nicer picture with the Canvas option then you can choose to push to a 3D PCB with canvas.
I hope this helps clarify the situation.
Best Regards,

Jorge Garcia
Product Support Specialist for Fusion 360 and EAGLE
Kudos are much appreciated if the information I have shared is helpful to you and/or others.
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