Because I've never heard anyone talk about it, and I talk to a lot of recruiters, both internal and external.

Did you ask them about it? Maybe it's not something they just bring up?

Also external recruiters don't use autolatric filtering systems since they usually just fish people via LinkedIn. It's mostly the companies own application websites that use these systems as they're the ones getting spammed, not the external recruiters.

Given that I've hired a bunch in big tech so have been talking to recuiters very often (and that I've done LinkedIn sourcing for said companies) I honestly don't think this appears to happen in Ireland.

Which is odd, maybe something to do with the fact that Ireland isn't in Schengen?