I'm skeptical about tariffs and I'm not
necessarily opposed to subsidies (although I do kind of question whether they are actually an efficient way to help income-challenged Americans) -- but we could still distribute those subsidies differently in order to cheapen healthier food that's in our better interest to encourage. We could also, if we're getting rid of subsidies, consider giving income-challenged people money directly, which may or may not be comparatively cost-effective to working directly with the industry.
So there's a lot of avenues that we could take, and yeah, eliminating food subsidies entirely and not giving any other kinds of aid would probably be a mistake. I'm not disagreeing with you. It's just... there's a lot of things we could change or try that wouldn't leave people to starve. Recognizing that meat is subsidized opens up doors for us to talk about whether our current system is efficient, about what behaviors our current system incentivizes. If nothing else it at least acknowledges that we are currently messing with the market, that meat prices aren't naturally low, and that we if we're comfortable with that kind of intervention, then we could at least mess with the market in different ways to promote more diverse foods.
Right now, we are artificially boosting a few segments of the food industry to frankly unhealthy levels of consumption (at least in most of the US) in order to help people afford food. It is worth considering if it is possible to help those people without propping up industries that are at least indirectly responsible for a nontrivial number of health risks and environmental challenges in the US. I don't think most people here are saying we should leave income-strapped Americans to starve (or at least I'm not), but like you said, the current status quo isn't really working, and it has some some pretty big downsides.
Even if you don't want to touch subsidies at all, at the least we could talk about stuff like checkoff programs. I find it much harder to argue that government intervention into how food is advertised is for the benefit of low-income Americans, and I think the advertising that comes from that forced tax on food is responsible for some increase in consumption.