What? Have you ever heard of soy, beans, lentils, chickpeas or the huge variety of seeds? You don't need meat to get your protein, as many eastern folks have proofed over many many years.
[0] https://veganhealth.org/taurine-and-carnitine/
[1] see "Creatine for Vegans" https://www.fitbod.me/blog/natural-food-sources-creatine
Many of these new sources don't have complete protein profile needed to be healthy.
It's possible to have a healthy vegan diet but it's a lot of work because you have to look at what amino acids and various nutrients are missing. It's much easier to just add meat to your diet. And anecdotally, a lot of vegans buy the "healthy" marketing and don't even pay attention to things like amino acid profiles. Which is unhealthy and frankly dangerous