That does not make it illegal to unlock a phone. Is there any case law supporting the notion that unlocking a phone actually is a DMCA violation, or just the carriers claiming that it is (possibly in settled lawsuits)?
Also the POTUS, the US Attorney General, and the law.
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> Is there any case law supporting
Yes.
Neither uninformed skepticism nor demands for us to do your research for you while holding up zero evidence of your own validate your position.
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> or just the carriers
Seriously, try hitting Google once or twice. This is hard to watch.
It does cite case law that points in the direction that the DMCA is only triggered when the lock protects a creative work, which cell phone access may not be. Considering how carefully the EFF tracks these things, if there was case law supporting the carriers' (and possibly executive branch's) position, they would mention it.