Meat is easiest because it's sold everywhere. Where I live, someone makes a variety of vegan convenience food that they've managed to get stocked in 7-11s all over the place. The food is all comparably priced to meat-based equivalents (this is stuff like "vegan bbq pulled meat hand-pie") but completely plant-based.
If you ate one of those, you'd find it as filling, tasty, and satisfying as something meat-based.
In fact, eating those (just out of curiosity) was the thing that even opened me up to a meat-free diet, because before that, I'd had friends serve me tempe, tofu, etc., and man that stuff is a bad introduction to a plant-based diet.
If you added a tax on meat to where the tasty, high-quality plant-based thing being sold at the 7-11s was now 20% cheaper, people would switch and not even think twice about it.
The problem is that, up to now, people package plant-based food as part of a lifestyle, and not just something tasty to stand alone on its own. Hopefully the impossible burger and beyond meat close that gap, too. You shouldn't need to be a straight-edge hardcore vegan to eat only plants 6 out of 7 days of the week.
