As a Linux/Windows developer you are not the target audience (which I already addressed).
Besides, just because you can't use it, it doesn't make it a toy language, just a language that doesn't have support (or full support) for Linux.
A toy language has a specific meaning, it's not a generic work for "language I can't use professionally on my platform/industry".
I can't use Forth to make web apps either, which is were I make all of my money, but it's not a toy language by any means.
As a developer for Apple platforms, am I right to consider C# or Java toy languages, too?
C# that he mentioned wouldn't be toy languages even if there were 0 Apple and Android C# apps. It would just be a totally professional Windows language with no Android/iOS support.
C# was professional even when it only supported Windows (and partially FreeBSD), before Mono came along...
As well as the decade-plus when Mono existed but wasn't owned by Microsoft, making cross-platform support merely incidental or even a negative from Microsoft's perspective.