Nah, there's nothing in this. There are so many distinctly divergent characteristics that they would have nothing to stand on.
Of course, facts won't stop greedy assholes from making stupid decisions.
please stop blaming this on greed...
Part of owning IP is that you need to defend it.
Let's imagine a scenario where a company had a set of armor that was visually recognizable. Similar to how Stormtrooper armor or Space Marine armor, is visually recognizable and heavily associated with their company.
Now, let's say that I form a computer game company, or start drawing a comic book that I am selling and profiting off of, etc. It's minimal amount of money, but it's still something.
In that new property, I am using images that are have a similarity to, but not
quite the same as the armors that are used by Disney and Games Workshop
If Disney and/or Games Workshop become aware of it and decide that "the juice isn't worth the squeeze" from suing me, they open themselves up to a problem...which is another company can make the argument that these companies have abandoned their trademarks and that they are now free to market direct copies of the (formerly) trademarked items and are allowed to make a profit from them.
Before you start celebrating cheaper prices for these items though, think about the consequences. You are less likely to see new content from these companies. After all, a lot of these models fund development of new model sets, revised rulesets, new IPs, etc. Eventually, companies like GW would go bankrupt, and without something like a marketable line of owned IP, it is highly unlikely that any large company (say Hasbro) would purchase the property. Any company that does purchase it (if any) would be small independent companies that won't have the resources to do much more than provide older additions online in PDF mode. Broken rules won't be fixed, new products, campaigns, or systems won't be developed.
Owning an IP means defending it. Cease and Desist letters and even lawsuits are common, even if there is little merit because they need a definitive ruling or agreement they can point to that says "no, this IP does not infringe" so that the next time someone else does something, they can't point to the other IP and say "they didn't defend it last year, so they abandoned it"