RISC-V is from a significantly differing category. A category for WASM doesn't really exist yet, there is nothing else like this -- a relatively low level bytecode language with high-level features such as nominal types, garbage collection, modules.
IMO such a category existed for quite a long time, JVM and .NET all falls into this category. Yes WASM has its fame for becoming a browser standard, but fundamentally, there is very little difference between WASM and JVM.
JVM has objects as the basic building block. For WASM it's linear memory(ies), so it's lower level, and was created from the start to support languages like C/C++. .NET indeed looks quite similar, given that it supports C++ compilation, tough I'm not familiar enough with the compilation model to draw comparisons.
