In WWII it was famously true that fighter pilots would fiercely argue for the absolute superiority of whatever plane they had been flying for a few months. For example, Thunderbolt pilots hated being moving to Mustangs (etc) - even though to our eyes the Mustang is obviously a superior plane.
Once your instincts adapt to something intimately (and programming languages require that); that's what feels right. You'll argue vociferously against a change and use what are objective reasons. (The Thunderbolt could dive faster, it was a brick.)
Of course, in the United States Army Air Force, you still had to switch.
The old hands usually remain convinced of the superiority of what they know, and irritated by Young Turks telling them something else, nicely or not. Because the Young Turks can't be right. But they are, often.
Programmers love language wars.