The safeguard is "you go bankrupt if you fuck up"

Imagine there was some way for a trading company to execute billions of dollars of trades and they say "ooops, sorry, that was all a mistake" can you not see how that would be abused?

Now, the story also says that within a minute of the market opening, the experienced traders knew something was wrong. Do they bear any culpability for jumping on those trades, making their money off of something they knew couldn't be intentional?

This isn’t really correct. Typically exchanges have safety parameters which market makers can set according to how they wish to trade, and if you exceed those your orders will no longer be accepted and existing orders may also be pulled.

Obviously there are false positives occasionally and there is typically communication between the exchange and the market maker to ensure those don’t reoccur.

A safeguard doesn't have to be a revert.

A safeguard could be rate limiting. And or the ability to disable an API key or whatever the equivalent is.

This actually seems pretty reasonable to me.

It's interesting to note that exchanges are adding "obvious error" rules that can slash trades under certain circumstances.