There's nothing small and tactical, about fighting off a Tyranid hive fleet invasion, or a massive Waaaagh.
Except the number of models per side, how important terrain and individual model line of sight is, moving individual units rather than entire blocks of units, how units are moved more like skirmishers each moving around the board on their own rather than as a block (kept at least 2" to another model in the unit), and so on.
Fantasy works much better with the Total War mechanics. They're practically made for each other, with unit blocks, wheeling, flanking, and so on.
How would 40k even work with Total War mechanics? 100 Space Marines are going to line up in a rectangular block and walk at 1000 orcs lined up in a rectangle marching straight at the Space Marines? I mean, I get the desire but Total War fits perfectly with WHFB, not WH40k.
Epic 40k makes sense. It takes a very high level abstract view of the modern battlefield, observing entire formations of tanks, battalion movements, and so on. At that point a "modern" military force sort of resembles the more classic "unit blocks" wargame.
Or maybe they can say "hell with it" and just shove all the WH40k units into block formations. It'd be sort of silly, but Warhammer is sort of silly.
((((
