I see such claims all the time, and they are misguided.
To generalize a bit, it’s best to eat foods that are as unprocessed as possible.
To quote the Harvard School of Public Health, highly processed foods “go beyond the incorporation of salt, sweeteners, or fat to include artificial colors and flavors and preservatives that promote shelf stability, preserve texture, and increase palatability. Several processing steps using multiple ingredients comprise the ultra-processed food. It is speculated that these foods are designed to specifically increase cravings so that people will overeat them and purchase more.”
If you are eating highly processed plant-based foods, you are eating an unhealthy diet. Think: fake cheese and fake burgers.
Eat foods that are BOTH plant-based and minimally processed. It’s good for you, and better for the planet (but no one is going to “save the planet” based solely on what they eat). Overblown claims are unhelpful hyperbole. Small, steady steps in the right direction make the most sense.