The problem with cultured meat is that it doesn't taste or feel like meat. Meat only gets its taste and texture because the creature has had stuff like breathing, blood flow, exercise etc etc. It's be more like meat pudding.
Also, you may have noticed that it needs lab equipment to be made. How the hell are the people in Africa going to get that? And even if we in the first world use it, it won't end up in the massive surplus for the rest due to corporate interests. (See the entirety of the diamond industry)
Finally, it's not going to result in happier cows. Those farm animals are bred to be eaten, that is literally their purpose in life, and they have pretty cushy lives right up until they're slaughtered. If millions of meat and fish farmers were suddenly told '"Yeah, we're not using them anymore, we're growing meat in labs now" you think they'd just shrug and let the animals free? Hell no! They'd just kill them all so they don't lose astronomical amounts of money feeding the (now useless) things, and most will still probably go out of business and lose their homes as their livelihood becomes redundant.
tl;dr You can't suddenly advance technology unless culture keeps up with it, even if you think it'd be a good idea. It's that sort of thinking that led to the horrendous loss of life in WW1, and is probably one of the reasons so many are sceptical of solar power today.