I mean,
If the airplane fly at 300 Kt True Air Speed and there is 20 Kt of headwind, it means it will be flying at 280 Kt ground speed.
On the other hand, it the same aircraft has a 20 kt of tailwind, it will be flying at 320 Kt ground speed.
Anyways, all of two true air speeds will be 300 Kt, but in the first case the airplane engines will produce less thrust, isnīt it ?