They used to happen.

"Meet your match" was the absolute worst update to a game I've ever seen. The outcry was so bad Valve even bothered to reply to comments on reddit and other forums for once.

Instead of rolling it back and actually talking to and listening to the community like they should have done and trying again later, they doubled down and tried to fix the multiple bugs they introduced and didn't revert any of the unpopular gameplay changes.

TF2 is still just about good enough that it's an enjoyable game, but it's dying a slow death due to all the bots, cheaters, and the absurdity that is "random crits"