I'd be willing to believe that removal of a license file could be accidental. However, what is being discussed here is wholesale replacement of a license notice in multiple files, which is much harder for me to believe is a mistake made out of ignorance or stupidity.

Don't you have to be pretty ignorant though to strip out the old license and then just replace it with another one? I mean you have to consciously do it.

Then now is his moment to learn about open source licensing. Doesn't mean the infraction does not count or we should let it slide. As any license, even MIT with its few requirements must be enforced to be worth its bytes.

Hanlon's razor is my favorite razor and the one I find most true in day to day life.

Disagree, the forked repo would have to intentionally delete the license data.

Ignorance would be misunderstanding or even misrepresenting the actual license with the wrong license. I maintain a FLOSS project that ships libraries with various FLOSS licenses, and it's within the realm of possibility that somewhere in there is a README that conflicts with the license at the top of a corresponding C source or header file. (Hypothetical example: README says gplv2 and the c file is 3-clause BSD.)

But removing a copyright where condition #1 is a single sentence that tells you not to remove the copyright? And replacing it with a different license? That certainly isn't ignorance.

An ignorant person would ignore a license or just delete the license text. But he didn't just delete it, he replaced it.

Doesn't Google go after people for doing the same thing?