First - they are not healthy. They have loads of fat/sodium etc. They may have lesser sat fat but that's just one parameter. They were not designed to be healthy.
Second - their prime value is that they can mimic taste of meat. They still fall short of that. Impossible burger still do not have the smell of beef burger.
Given they fall short of what their core value is - it is amazing they sell 2-3 times the price of meat products.
These have a future if they can retail one-third to one-fourth price of actual meat.
Since they don't - they rely on psychological manipulation - trying to induce guilt in to meat eaters. These are corporates with excellent media relations. So you see a lot of articles of dubious science on how meat is bad for environment and you can save planet by eating their overpriced garbage.
got tricked into having one (Called Rebel Whooper here in Australian Hungry Jack) by my wife, $7.45 (Less than $5 USD) for a burger + fries + coke. Wasn't that bad but you know there are no meat in it. Probably different recipe