You've got cause and effect flipped here. It's not the bitterness that causes one to be not hired, its not being hired that causes bitterness. I experienced the same when trying to get in the field. The narrative at the time was that there was a labor shortage, and they were trying to push for more H1B visa holders. Yet there were very very few entry level positions, nobody was training, and the company that hired me paid horribly($12/hr) and didn't teach me anything. Keep in mind, I had recently graduated from university in the field.

For decades, employers had far more leverage than employees. Now that that's eroded a bit, everyone is panicking. But this is exactly what is needed to employers to actually train and care about their workers.