For most products, and virtually all that aren't particularly modern, they suffer from being set up as direct replacements for meat. Take fake deli meats, for example. There are options that make a good sandwich. But they don't make a good $specific-meat sandwich. If they found a way to position themselves more in the vein of ham vs turkey vs plant-based sandwich they would do far, far better. Instead they position themselves as fake-ham or something, and then some unsuspecting person trying out plant-based alternatives goes in expecting a ham sandwich and ends up with their expectations rather violated. People don't like that, particularly with food. But they went in just expecting some kind of sandwich, I think they very well might enjoy it.
I've been vegetarian-tending-towards-vegan for over a decade and I still occasionally fall into that trap if I'm not careful.
Products like Impossible are the exception. They are so notable because they are getting into the realm where a direct comparison with meat actually works in their favor. I think that's great. I think you are right that this is the key for convincing many people to move away from meat. It's so much easier to market something as another version of meat, rather than a whole new thing. But I also think it's worth keeping in mind that they are exceptional products, and what works for them may not be the best for others.