The term rip-off to me means deliberate infringements of a company's patented designs. If that can be proven, then there is a case. If not, then it's not technically a rip-off. But then I'm not a legal expert.
The point is, there is not much plainly visible that won't be already an industry standard. The exact material composition (which is unique to a bg extend) I do not consider as "plain visible", the arctube shape is visible but no way anything new.
Plus patents (as legal tools) are in fact design publications, which offer monopoly protection only for limited time, which is already out, given how long these lamps are here. So even when copied, there is nothing bad on it.
On the contrary, patents were originally invented mainly as a way to encourage spreading and publishing the knowkedge, with the limited time monopoly benefit as an incentive.
The way how the patents are utilized today (to mainly prevent others from advancing by claiming very often just obvious ideas) is their abuse.
And when taking rigorously according to the original purpose of patents, 99% of them should have been thrown away by tye ofice from the start (for a patent to be valid, a thing should be NOVEL, NOT OBVIOUS, it should be accompanied by THOROUGH and UNDERSTANDABLE explanation). Mainly the last two (Obvious and Contain explanations) are the most abused. Mainly exploiting the impossibility of the patent office representatives to have the required expertize about all subjects they have to deal with...