That would be amazing. Looking at the prices for vegetarian and vegan meat substitutes, I can't see it happening. : They are more expensive than meat. It appears that we need a lot more competition in these markets.
You'd remove the incentives to choose one over the other but less people will be able to eat. That's dangerous.
More over, you'd remove the new tech's incentive to become cheaper. I think cheaper food is always better for everyone.
Ideally it should scale a lot better than the real stuff.
Pricing in the negative externalities of meat is the best way to address this, which has a started goal of reducing the consumption of environmentally harmful meat.
It enables meat that is sustainable to be priced competitively and to shift consumption, but we should be very honest -- the goal of any pigouvian tax is to reduce the consumption of the harmful product.
Thus, meat should become more of a luxury, which means yes, it would be less accessible to the poor. But with billions becoming richer and demanding more meat consumption, the path we are on is entirely unsustainable.
The aim is only to nudge the scale rather than tax the farmed meat out of existence.
If we want to make sure meat products stay available in large quantities to everyone so you can have bacon for breakfast, a sandwich with deli slices for lunch, and a burger for dinner every day, you can take that subsidy money and put it toward lab grown meat instead.
Personally I'd like to see some of it redirected to vegetables though. Cheap meat and expensive vegetables isn't the ideal outcome even if it comes from the lab.
For the soy at least.
The issue is really eating processed crap off the shelves than the ingredients as per se, e.g. does any get obese from fresh pasta?