That does not make it a defacto winner for any other problem space. For games, for example, having to reason about concurrency is the status quo for most of the gameplay code regardless of the memory management system, and tightening memory only addresses a fragment of the problem space, because dynamic memory allocation is not a primary requirement(fixed sets of assets and fixed design constraints mean that a heavily static, early-binding approach to game coding works for most things, most of the time - so the difficult errors will tend to surface outside of memory management as an odd runtime behavior). [0]

As a drop-in "better C" it's not a great fit, either, because the focus is on making these in-the-large problems a top concern at all times. It creates friction in migrating to Rust, leaving the floor open for a smaller language that operates at the lowest levels of safety, doing its best to be both C-compatible and improve the parts that can't be addressed by leveraging or patching up the existing C ecosystem.

Zig is my top pick for a language that can address this niche, though it's still an early stage project.

[0] AAA-scale code can still benefit, of course. Most games aren't AAA.