However, the web also has a terrible bloat/legacy issue it refuses to deal with. So sooner or later, a new minimal platform will grow from within it, the way the web started in the 90s as the then humble browser. And the web will be replaced.
First, it's explicitly designed to be easy to port existing software to. Like C libraries, say. Sounds good right? Well, it's not designed as a platform that arose from the needs of the users, like the web did. But the need of developers porting software, who previously compiled C libraries to JS gibberish and had to deal with garbage collection bottlenecks etc. This seems fairly narrow. WASM has almost no contact surface with the rest of the browser, aside from raw compute. It can't access DOM, or GPU or anything (last I checked).
Second, for reasons of safety, they eliminated jumps from the code. Instead it's structured, like a high-level language. It has an explicit call stack and everything. Which is great, except this is a complete mismatch for all new generation languages like Go, Rust etc. which focus heavily on concurrency, coroutines, generators, async functions etc. Translating code like that to WASM requires workarounds with significant performance penalty.