Well first of all there is tons of research being done right now into linear type systems, which have the potential to statically verify a whole bunch of things

Well first of all there is tons of research being done right now into linear type systems, which have the potential to statically verify a whole bunch of things that Rusts borrow checking still struggles with. It's a very hot field of CS research atm. I also think that you discount the amount of advancement that has been done in the development of pauseless GC. It's a shame that many of these are only available on the JVM (and sometimes only at a steep price), but I have no doubt the main ideas will eventually get adopted by other languages. But really there are so many unexplored niches. AFAIK no current architecture has hardware support for read/write barriers, having that would make pauseless GC much more feasible. Zig has been experimenting with letting people use custom memory allocators, but there are many more avenues there that have not been explored. Why not have a language feature for "this value lives outside GC management" similar to Haskells compact regions but more powerful? Nim has some cool ideas about mixing reference counting for most values and a more general GC for cycle breaking. Mixing GC and non-GC values is also still a seriously underexplored field IMO.