Not yet, a note on the Memory instructions [1] still says: “Future version of WebAssembly might provide memory instructions with 64 bit address ranges.”
Perhaps... but 5 years without progress in some areas is an eternity. Rust in Firefox was super interesting and they run out of funding. It is really hard to explain to a client: "your application would work on WASM, on a browser, with no installation, but it will not scale in time and memory, and there is not a clear roadmap of then things will improve (despite OS and compiler guys know how to fix those things)".
I fear they will run out of gas before the interesting features there are completed...