Maybe dumb fuck should get on Google (before he reports them for criminal behavior)
First two results say.. Nope.. they are NOT illegal.
https://www.refog.com/is-a-keylogger-legal.html
https://answers.yahoo.com/question/index?qid=20080110072903AAaFDKh

Apparently the world agrees..

If you think keylogger can cause harm, well everything can as well - you can use an axe to cut your thumb or to build a house. You can use a fire to burn your neighbour or to get some warmth.