“For some reason the idea that Christians are monsters has occupied traditional Jewish thought for centuries.”
Yes, that goes hand-in-hand with 1900 years of forced conversions, murders, expulsions, kidnappings, enslavement, deprivation of basic human rights, etc.
Any more Christian love like that, and we’d be wiped out.
Now, are Christians in the USA of the 21st century different? Yes. Indeed. Wonderful people.
The only reason you say wonderful people is because you are in the middle of them and it is also a media age where things actually get recorded for posterity. It’s harder to ignore the good. The bad existed, but the good always outweighed it.