Ohh, deja vu. I just had this exact discussion but about Transformers. Same thing there - "Hasbro doesn't meet the demands of the userbase so it's totally okay for others to infringe on copyright and produce the stuff that the fans really want". Sorry, but no. I'd like to see Lego produce every character available and sell them for $1 each, but that's not happening in the real world. That doesn't mean that I feel okay with buying knockoffs. If I really want something that doesn't exist, I can try to build it out of existing parts or I can customize it myself. If I get non-Lego, just to fill out my collection of Lego figures... well, what's the point? Why even bother to collect Lego at that point?
And while there's no reason to expect that the transparent Iron-Man is stuffed with lead paint... it's pretty damn reasonable to think that it could be. Lego is one of the safest (and most expensive) toys around because they have standards and a reputation. Random Chinese workshop doesn't and hasn't. It could be good stuff, it could be anything. But if they don't care about IP infringement, why would they care (much) about safety? Also, who profits? In other knockoff businesses, situated in China, there's often organized crime. Sure, it may be scaremongering to say that your Aliexpress Hulk finances extortion in Shanghai somewhere, but can we be sure? They're doing illegal business to begin with, why stop with toys? Is there some code of honour? "Sure, we pirate commercial goods but we would never associate with ACTUAL crime!"
It's your own money and it's probably not a lead hazard that finances crime (probably). I just feel like I don't need to pad out my already packed figure collection with worthless copies. I'm quite happy with my $30 Chell, thank you.