I did a RIIR again and:
Two apps nearly-identical in functionality now. On startup, before processing anything:
#Rust + #Axum: 3.5MB RES
#Elixir + #Phoenix: 75MB RES
Literally 20x difference, and I haven't even benchmarked throughput/perf. For a use case where a big goal is extremely low resource use, this is huge.
(both of these are running in release/prod mode btw)