You are of course right that Ilford will probably only recommend their own developer...but as a counter example i remember my favorite paper of all time, Forte Polygrade, came with instructions recommending Dektol for neutral, Zonal for cool, and Edwal Ultra Black for cold tone.

Now, it is true Forte didn't have its own developer (although there did seem to be a partnership with Zonal), but nonetheless what a fantastic way to respect its customers to give this information.

Of course if Ilford offers its cool tone developer they needn't bother - i think we would all gladly use it - but if not info on different developers would really be appreciated...just like Forte