I'm not sure I understand this argument. The point is that there are some serious issues with the production of meat that are not (or may not be in future) issues with lab grown meat.

It's true that you could solve this by only eating legumes, but you then go on to say you don't even eat only legumes yourself, you also consume meat. So for those times where you do consume meat, lab grown meat would solve the issues that come with that.

Totally get that you may have dietary/taste preferences that preclude consumption of these meats, but that sounds different to the OP's point that they potential solve a lot of issues with our current food supply.

I consume very little meat, and when I do it is either because someone serves me meat at a meal or occasionally I will buy some meat from my local butcher which sources their meat from local free range farms.

Meat consumption is also not a binary decision, you can consume 10% of the meat you currently do and reduce the environmental side effects caused by your meat consumption by 90%. Furthermore, you can consume meat that comes from small scale local sustainable sources to further reduce your footprint.

It is the same deal with eggs, I don’t buy factory eggs, I buy them from my local farmer who has free range chickens. Sure, eggs are $8/dozen, but that is the real cost of eggs which do not preclude animal suffering and unsustainable farming practices.

My point is maybe the solution to the meat supply issues is to consume less meat, and consume meat from more sustainable sources. It is almost impossible for western society to grasp that maybe the solution to sustainability problems is to align their consumption with the rest of the world instead of turning to technology to solve all their problems. It is the same with so many other things like water management where the solution seems to be to dam more rivers and suck more acquifers dry instead of maybe not trying to grow grass and cedar trees in a desert.