It's not an opinion. It's a simple matter of observation. I see software all around me (and I write some of it) written in C/C++/Java and other imperative languages scaling perfectly fine on large scale multicore systems. I use linux, OSX, Android and iOS on a daily basis. Almost all the code running on these boxes is written in imperative languages, much of it written as parallel, shared memory code.
Google (where I used to work, but I don't think I'm revealing any secrets here) runs a gigantic cluster on foundational software almost entirely written in multithreaded C++ with the kernel written in C of course (some of the application level stuff is in other languages, but still a whole lot even at that level is in C++). Almost any large scale, parallel computational systems you could name are written in imperative languages.
To call all of the above "just my opinion" is simply denying reality. There's no further argument to be had unless there's a basic, shared reality ground to stand on.