This turned out surprisingly well:
In the harsh light of the Electronics Workbench, you can see there’s less than meets the eye: a single knockoff Neopixel taped to the back side of the bulb just below the equator and a knockoff Arduino Pro Mini taped to the Mogul lamp socket:
The electrical box serves as a base and the cord doesn’t do anything in this incarnation.
The 5050 SMD LED package (inside an ugly 3D printed plate cap) looks enough like a point source to shadow the filament & support structure against the frosted bulb. The blurry upper part of the filament is closer to the LED, which isn’t really a point source and must fight its way through the frosting.
The Pro Mini runs the same firmware as the Bowl o’ Fire floodlamp, of course, dialed back for slow fades.
It lights up the room something wonderful …