> I actually think Java is the better PL, but the worse runtime (in what world are 10s GC pauses ever acceptable).

This seems like a very odd/outdated criticism. 10s CMS full STW GCs are a thing of the past. There are low-latency GCs available for free in OpenJDK now with sub-millisecond pause times. Where I've seen the two runtimes compared (e.g. Coinbase used both langs in latency-sensitive exchange components) Java's has generally come out ahead.