The human body is adapted to consume and digest all kinds of food. Humans are omnivores, not herbivores or carnivores.
You can eat healthily on a vegan diet but it requires a lot of planning to make sure that it is not deficient in many key nutrients including calcium, iron and zinc, while vitamin B12 is almost entirely sourced from animal products.
The difficulty is that whenever someone decides on a particular diet aimed at good health, good health is usually the result because people who are concerned about being healthy usually have healthy lifestyles, across the board, regular exercise, keeping their weight down not drinking heavily etc etc.
There are also many examples of people not thriving on a vegan diet. A vegan diet can also be highly dependent on highly processed foods, the UPFs, that we are meant to keep to a minimum.
In a time of food plenty (in most countries) where we can make infinite choices about what we eat, there are many ways of eating a healthy diet and staying healthy well into old age.
Veganism suits you and makes you happy and content, I note you run the usual old hackneyed emotional blackmail about dead animals, have you ever considered the billions, and trillions of insects, small mammals, micro organisms etc that are killed growing crops?