Whatever diet you follow, if you don’t care about what you eat or don’t eat and in which combinations, your health will not be what could be expected for a person of the same profile who cares about what they eat.
Processed (also called “junk”) foods aren’t going away, whichever diet you look at. People want convenience. Try telling someone to change their diet to be different from what they’re used to eating and you’ll find out how difficult it is (without other motivations, external support, convenience of picking stuff off the shelves or ordering something, etc.).
Considering the environmental impact of meat (and the current agricultural systems), and considering that it’s absolutely impossible for everyone to avoid their supermarkets and convenience foods, these alternatives provide some kind of stop gap even if they may be unhealthy. Point the drawbacks. Give feedback to the makers to improve the products. But don’t pretend that the currently available junk foods (that aren’t vegan) are better overall, all things considered.
Personally, I avoid processed and junk foods most of the time. I also cook food by myself almost all the time. But I do indulge once in a while on some junk food. And I can feel its adverse effects. I’m under no illusion that this would be the same for others or even possible for others just because I’m able to do it.