Recruiters ghosting/blocking you - the new norm

How common is it for recruiters to ghost you after multiple rounds of interviews and assessments (over months) by blocking your email so you can't even send follow up emails?

The way I see it - they don't lose much since they have thousands to choose from an applicant pool, but it certainly undermines the effort made my candidates to a huge degree.

Or is that common courtesy, acknowledgement and in general being decent human seem rathee utopian concepts in this day and age?

Wouldn't wish it on my worst enemy.