Cuprajake - if some grinders cost £2k if not more, I can’t see why someone wouldn’t spend £500 on a filter grinder and another £500 on a Niche. There you go… £1k saved. 😉
But that’s not the point. The point is why then have grinders which are “all purpose”. I get for the odd person who makes a filter brew once in a while, but for those who drink often, then they might not be getting the best? As Dave said above, geometry of burrs are focused on a brew method. Having one burr which can do them all is possible, but you won’t get the best. As the saying goes… Jack of all trades, master of none.
And as I said above… if someone could come up with a concept where the burrs could be easily interchangeable, without one having to unscrew the top, remove top plate, remove top burr, remove lower burr, align… something where you could easy drop in one or the other ina matter of minutes without having to dismantle much, then that would be an incredible selling point for an “all purpose” grinder.