I think "burning a book" in itself isn't bad, as in A book, it's the principal of the thing. Fahrenheit-451 used it as the most powerful symbolism (though IMHO, a bit ham fisted).
Many Far-Right groups throughout the 20th century have held book-burning events as a very open and dramatic way of expressing their anti-intellectual attitudes. It's demonstrative of a mindset that is not to counter the opposing argument but to literally destroy the medium of it by force.
It's the ultimate troll move.
But goes the concept of book burning really apply in this modern age?
Book burning in Nazi Germany works by the Nazis going out to the community and in a kind of "bonfire of the vanities" imploring them to bring out all their books, films and recordings all their HARD MEDIA that the previous nazi rally had cast as a corrupting influence particularly on deep and complex ideas.
One think I've discovered about the Nazis studying them is they didn't really have philosophy that could be debated on equal terms, they didn't really have an argument, they just had an ideal and learned that if they could shout it loud enough, rouse the emotions enough, and succeed in crushing intellectual opposition then they could thrive. It's politics of the primitive brain.
White Power is just yelling "WHIIAAAAT POWARRR" with animalistic intensity and whipping up the base emptions of racial conflict. All the "philosophical arguments" for right-wing superiority ONLY work once all opposing argument have been PHYSICALLY crushed. In other words all these Nazis could only preach to the choir about 'Aryan supremacy' if their bully-boys physically silence anyone from pointing out what bollocks that is.
But how many of us get our information, ideas and philosophies from books any more?
With the internet, the computer revolution and the EXPLOSION of storage capacity not to mention translating and encoding technology mean books are obsolete.
The WORD is what matters.
I'd say the modern equivalent of burning books is what China is doing with the internet, though it falls far short of the worst of nazi excesses as it has not succeeded in rallying large parts of the population to assist in the cultural mutilation... or at least not to the same extent.
It seems China's government is in a cold war with it's people, they constantly want to know more and the government keeps withholding.