Unable to set primary constructor for Symbol.newClass oversight or intentional?

Symbol.newClass seems to automatically add a Symbol for a parameter-less primary constructor and there doesn’t seem to be a way to change it.

The best I could come up with is to use the compiler types directly:

    val ctorMethodType = MethodType(paramNames)(paramInfosExp, _ => cls.typeRef)
    val ctorSym = Symbol.newMethod(cls, ctorName, ctorMethodType, Flags.Synthetic, Symbol.noSymbol)
    cls.asInstanceOf[dotty.tools.dotc.core.Symbols.ClassSymbol]
      .replace(
        cls.primaryConstructor.asInstanceOf[dotty.tools.dotc.core.Symbols.Symbol],
        ctorSym.asInstanceOf[dotty.tools.dotc.core.Symbols.Symbol]
      )

Is this an oversight or was it left out intentionally?