I really like both but the more fantastical wins out because it eliminates the "knights die out and guns win" history aspect.
That always left a sour taste in my mouth when playing history based games or low-fantasy genres. Eventually that medieval world and it's glorious knights will be replaced as time goes forward.
Then you have dark fantasy settings like Warhammer and Dark Souls that makes the matter moot because everyone's going to die before any industrial age is made. Which is the only consolation I had with my Bretonnia obsession and Empire fans said they'd eventually win due to progress, it didn't matter because the world was always doomed.
So yeah, for a non-dark fantasy it's whichever setting can make it so gun armies can appear but never play a dominant role or crush the competition like in a setting where mountain-sized monsters or even gods can appear and heroes with magic weapons are needed to slay or repel them.
Besides that I like high fantasy settings because of how they push the boundary of imagination on what can happen in the setting.
Knights watching over a castle to repel a aggressive neighboring country is good but knights watching over a castle made from the stone-like bones of a titanic dragon their founder slayed and use it to either seal it's cursed and vengeful soul or hold off armies of giants drawn by it is even better.