Sure they do, computers repeatedly, quickly, and predictably do what they are programmed to do. Which includes any human errors in that programming.
And now they predictably do what they are not programmed to do.
Sure, there's some math that says being really close and exact arn't a big deal; but then you're also saying your secrets don't need to be exact when decoding them and they absolutely do atm.
Sure looks like a weird privacy veil that sorta might work for some things, like frosted glass, but think of a toilet stall with all frosted glass, are you still comfortable going to the bathroom in there?
The use case for this is that many enterprise customers want SaaS products to strip PII from ingested content, and there's no non-model way to do it.
Think, ingesting call transcripts where those calls may include credit card numbers or private data. The call transcripts are very useful for various things, but for obvious reasons we don't want to ingest the PII.
Credit card numbers are deterministic. A five year old could write a script to strip out credit card numbers.
As for other PII ? You're seriously expecting an LLM to find every instance of every random piece of PII ? Worldwide ? In multiple languages ? I've got an igloo I'd like to sell you ...