Programmer love is secretly (or not so secretly) the reason for all language choice. I say why hide it.

Not really. Domain often dictates. If AAA games could get away with using a garbage collected language, I'm sure they would.

Unreal has GC support for C++.

Unfortunately Unity broken GC is a side effect of them not wanting to improve the stone age runtime they are using.

I guess many AAA could actually be done in languages with GC support, but game devs tend to only change tools when the OS/console vendors force them.

All that is needed is having such a vendor pushing a language with the same effort as they are pushing for JavaScript JITs, lets say.

Programmer love would determine who'd make that change vs. who defended C++ to the death.

Domain is often dictated too—we're attracted to problems that fit our tools.

Not to worry, they will be forced for add javascript just to please the hordes of people who don't know any better.

Before that it had to be "VB like" scripting.

You forgot this part:

>and I have evidence that it has been objectively productive for me

He is fairly smart and has quite good taste, so I'll trust him to choose a good language.

It is logical for him to pick Racket because of these three points.

Only programmers would demand that you provide logical justification for an aesthetic preference :)

Ultimately, this is what art is. You need to go with what you love. 'logical argument' often just is a euphemism for rationalizing your convictions after the fact. You can't paint if you try to analyze every brush stroke. Let the subconscious flow.