there are different facets of lower arm strength.
pinch, grip, wrist, finger etc etc.
forearms make up a big part....but strong muscular forearms dont mean a good solid grip...it helps, but if you want a strong grip...train your grip. yes there is cross over between all the different types of strength.....but you can specialise and focus on a particular type
it all depends on your goals
If you need to use straps to deadlift, row or whatever....your grip is too week.