I feel like general purpose programming languages very widely already let you express DSLs, with semantics, names, structure, etc. appropriate to the domain. W

I feel like general purpose programming languages very widely already let you express DSLs, with semantics, names, structure, etc. appropriate to the domain. What they do restrict, to various degrees, is the syntax. So what we're talking about here is custom/customizable syntax to go with your DSL. That can be nice, but it comes at a high cost -- e.g., developers will have to understand the syntax, it will need to be maintained and extended as requirements grow or change. Of course it's worth it in some cases, and tools to help do it are great when it is. But I just don't see that there's a general problem that we don't have enough custom language syntax to deal with.