Some people like meat. They will pay for it. Unless the plant-based product is utterly indistinguishable from meat, I think many people will prefer meat. As long as there is consumer demand for meat, and it remains legal to sell, it will be made and sold. You may prefer something else, but other people will buy it. You cannot expect everyone to share your food preferences.
You don't like meat. I don't like tobacco. It definitely causes harm, and it has few redeeming qualities. I wish no one would buy the stuff. But, as long as it remains legal to sell, I expect people will buy it and smoke it, far into the future. We can't do anything about that. Our tastes and our opinions do not rule the marketplace.
Cultured meat will ultimately be cheaper than meat from animals. It will be cleaner, without as much contamination, bacteria or as many hormones. It will take much less energy and water to produce. It will eliminate the inhuman treatment of animals, and the slaughterhouse. (Although some people will probably demand the real thing.) So, in my opinion, it will be better for people, and better for animals and the ecosystem. I hope it can be developed.
I wouldn't know about that. Perhaps it is true. However, people do not always buy what is best to eat, or what is good for them. On the contrary, they buy a lot of "junk food" that is supposedly bad for you, with too much salt and too many processed ingredients. I wouldn't know if is actually as bad as portrayed in popular culture, but I can see that people eat too much and many are obese these days. In short, people are unwise. Even if plant-based food is better in a wholistic sense, people are sure to buy what is worse in a wholistic sense, including meat, so I hope it can be made somewhat less worse, and less destructive.