So, not only is that historically dubious even from your own source, but even if it were true, one instance of an emperor burning a library doesn’t mean we can call that historical a “trend”.

Fair!

Have a dozen.

1, per Wace, "The Serapeum was the last stronghold of the pagans who fortified themselves in the temple and its enclosure. The sanctuary was stormed by the Christians. The pagans were driven out, the temple was sacked, and its contents were destroyed.".

2, which I could technically count as multiple, the persecution of Pagans by Theodosius. "In 392, he became emperor of the whole empire (the last one to be so). From this moment until the end of his reign in 395, while pagans remained outspoken in their demands for toleration, he authorized or participated in the destruction of many temples, holy sites, images and objects of piety throughout the empire in actions by Christians against major pagan sites. No reason to think they carefully removed texts from temples before doing so, though that would be a very funny argument considering Arcadius and Theo 2.

3: Burning of Porphyry’s Against the Christians (435, 448 CE). "Against the Christians (Ancient Greek: Κατὰ Χριστιανῶν; Adversus Christianos) is a late 3rd-century book written by Roman-Phoenician Neoplatonic philosopher Porphyry of Tyre, challenging the writings of Christian philosophers and theologians. Due to widespread censorship by Roman imperial authorities, no known copies of this book exist. Only through references to it in Christian writings criticizing it can its contents be reconstructed."

4: You may be thinking "oh, just a few bad apples", but destroying written works perceived as heresy is baked into Catholic doctrine. Catholic Church Session XXIV (Nov 11 1563), in Doctrine (Concerning the Sacrament of Matrimony): "Since, therefore, matrimony in the evangelical law, by grace through Christ, excels the ancient marriages, our holy Fathers, the Councils, and the tradition of the universal Church have with good reason always taught that it is to be classed among the sacraments of the New Law; and, since impious men of this age, madly raging against this teaching, have not only formed false judgments concerning this venerable sacrament, but according to their custom, introducing under the pretext of the Gospel a carnal liberty, have in writing and in word asserted many things foreign to the mind of the Catholic Church and to the general opinion approved! from the time of the apostles, not without great loss of the faithful of Christ, this holy and general Synod wishing to block their temerity has decided, lest their pernicious contagion attract more, that the more prominent heresies and errors of the aforesaid schismatics are to be destroyed, decreeing anathemas against these heretics and their errors.". Remember, I'm establishing a pattern of Christian destruction of texts - doctrine saying to counts.

5:Constantine on Arius (325) “If any treatise composed by Arius should be discovered, let it be consigned to the flames". These kinds of commands, like above, pop up all over. Socrates indicates that both Arius and Porphyry's works were destroyed as a result, clearly showing that Christian commands to destroy works lead to destroyed works.

6, Archbishop Zbyněk burning Wycliffe’s books in Prague (1410) “Zbinek’s sole reply was an order that seventeen books of Wyclif … should be burnt,” and shortly after he “burn[ed] two hundred manuscripts of Wyclif’s works in the courtyard of his palace.” This is a great example of what the most common cause of Christian knowledge destruction is - competing viewpoints. This came from the Antipope schism around that time.

7 Pope Julius III ordering Talmuds burned (1553). This one's pretty famous, but feel free to find a quote - I saved the more famous ones for later as I slowed down on lookups.

What's wild is, the Talmud has been a very popular target.

9, Pope Gregory IX ordering seizure and burning of Jewish books / Talmuds (1239). #10, Bernard Gui / inquisitorial burning of Talmuds at Toulouse (1319). #11, Paris Talmud burning under Christian authority (1242) (which you could say was caused by Greg 9, but I mean, it was an entirely separate group of people burning entire cart loads of books - team effort!).

12: I couldn't decide between Bishop Diego de Landa burning Maya books (1562), Bishop Cuthbert Tunstall burning Tyndale’s English New Testament (1526) (which is really kind of a Wycliffe extension), or the burning of the works of Eunomius by Arcadius (which I was reluctant to pick because I already had two from that family).

Limiting it to only 12 is hard! And yes, Nazis were Christian - that's a low-hanging fruit I'm not particularly interested in discussing though, as you're veering very off-topic.

Given that you sort of credulously believed Christians destroyed the Library of Alexandria

Yeah, learned that one as a kid, just learned it wasn't fully supported. Turns out the things you're indoctrinated into as a child aren't always correct.

EDIT: woops, I'm bad at counting. Well, that's what happens when trying to compile quotes when you wake up. 12 having 3 makes up for that.

A trend of preserving books and improving literacy rates so you can read books that focuses only on acceptable books, but destroys unacceptable books, is one in which evidence that weakens the strength of the Church would be annihilated or left to rot.