People don't have to be 100% vegetarians. The real game changer is to get the world's population to reduce their meat intake by eating more vegetarian meals. Vegetarian meals can be very tasty and satisfying. There's no need for synthetic meat.
Fake meats take a lot of resources. It's just another way to make a buck by getting people to consume something they don't need. In the same way, as soda is nice to have but you don't want to get behind it as a way to save the world. Fake meats are equivalent to snacks not world saviors.