[Joe8Bit]

"Hard to write but easy for customers to deploy" is my guess. There are a bunch of very high-performance computing use-cases in finance (quant, HFT) that Java gets used for pretty routinely. That's a very attractive market to build primitives like databases for, they have very deep pockets, but you need to play in their ecosystem.

I've seen this "GC-less" Java in those use-cases quite a bit. From a conceptual design POV it's likely not the best approach, but there's a lot of sunk cost in that eco-system and a lot of trust and expertise where "Choosing a better language" is often several orders of magnitude more expensive.