I think I can understand why many ex-vegans cry or get highly emotional after they try animal products for the first time since their "healthy diet".
Their vegan diet is mostly just bland carb sources (bread, grains, rice, satan or however its spelt etc...) with insane amounts of sugary or savory sauces (think BBQ, ketchup etc...), which means most everything tastes the same.
They're crying or getting emotional because they have forgotten what genuine food tastes like; what actual fat tastes like; what actual meat tastes like.
If you've noticed all vegans say about their food is "it's soooo good, like, it's sooo good omg" or some variation of it. And they (or 90% of them) say it, kinda like some sort of cultish mantra (i.e. it's all fake and performative; to signal to other vegans "I'm vegan").
For food I really like, on the spot, I'll describe my appreciation in a much more unique fashion. It's not "soo good", it's "I'm going to die eating all this" good.
https://www.youtube.com/watch?v=GyzHTYv84_Y&ab_channel=TomLauris