Yeah I think “evangelical vegans” or “bad vegans” are a sort of caricature made for comedians and then everyone else to punch down on. Sure annoying vegans exist, and so do annoying meat eating people, but diet isn’t necessarily why these people are annoying.
I imagine there’s also an element of defensiveness from meat eaters as well. Even reasonably stating “I don’t eat meat because of the cruelty in the industry and the negative environmental impacts” is implicitly challenging a meat eater to consider those things, which they likely never have. And being faced with the certainty that the vegan is making that statement (the cruelty of the industry and environmental impacts are objective), the meat eater is possibly going to feel like they are being judged or attacked.
Depending on where you are sweet potatoes are often grown as an ornamental vine but the tubers are literally what you eat. You can grow them in the ground or in pots (I recommend pots so it’s easier to harvest, ymmv). Tomatos, blueberries, herbs, sunflowers, and strawberries are probably pretty easy to get away with too as long as you keep them organized looking.
If you don’t have an HOA and you live in its native range, central north america, the sunchoke is a crazy good source of food. Honestly too crazy, once you start growing it, it’ll be there forever and it’ll try to take over everything, but you’ll have the food there buried waiting for you year round. You can also grow it in pots, just be careful with the tubers and the soil, they will seriously spread out of control.