> What on earth is going on here?

With the nearly complete PR with the port to rust, a number of people predicted that it was going to happen. They were assured it's unlikely to happen and then they were accused of overreacting over effectively nothing. When those same people who were already upset about the rewrite, learned that their predictions the same ones that were rudely dismissed, were in fact, correct, they became upset again; this time about being lied to.

Correct or not, it's reasonable to conclude they were lied to. Especially given they correctly predicted the future.