[dangus]

And how big was that black market for incandescent light bulbs?

What would have happened to it when supply of incandescent bulbs dried up as manufacturers stopped making them?

Were there any homebrew incandescent lightbulbs?

You’re actually demonstrating my point here: when you ban or regulate something, there are a lot of things that go into whether a significant amount of people try to circumvent that ban. It’s not an automatic free for all thriving black market.

One reason not to circumvent a regulation is when it results in improvement of the status quo or when better alternatives to the banned item already existed.