Can you guy enlighten me what was wrong about it?
The anime specifically says that it was set in the 15th century. They even actually referenced the REAL person who came up with the theory in the 16th century at the ending
I don't think the fact that Christianity contributed to modern science in the 18th century erased what the Church did in the 15-16th century
In 1600, Giordan Bruno was publicly trial and burnt alive by the church because he defended Nicolaus Copernicus's views, he was the only person known to do so in the time period. That 1600 is set 200 years after the anime's setting.
I think most of the confusion are from people mistaking what happened to Giordan with Galileo. Galileo wasn't burnt alive, only house arrested, but the church defending and executing anyone going against their ideology in the 15th century can't be proven wrong with just "modern science was invented by Christians".
It took until 1822 for the Church to actually lift the ban on Copernicus's & Galileo's books lolw, they were absolutely controlling information and banning things that went against their doctrine.
Also I think you guys are confusing "Christians priests/officials" with "the Church". For me, it's more of a "Musician - Music Label" relationship. It's like tributing all of The Beatles success to Parlophone record label because they were signed to them. And very much like Music Labels, the Church went after people who illegally distribute Galileo/Copernicus's books. They might have yelled "Heresy" instead of "Piracy" but it's practically the same thing.