it can be done - asteroids and small to medium blocks ( large, too but at some point it looks stupid ) can be indeed be brushed aside by high mass ships ( supertrandports or capital sized ships )
the problem is that many ppl would disapprove, cause they feel that caps gained too much for no disadvantage then. - or in short, ppl want capships to suffer in asteroid fields
Ok. Caps, in particular larger caps, should have some degree of difficulty in asteroid/debris fields. Plowing through planetoids will slow anybody's progess.
On the other hand, much of the asteroids/debris could be blasted into to dust or pushed away by the mass of the vessel. Unfortunately, the game engine limits our options in this regard. Disco's ateroids/debris chunks are unmoveable and impervious. This, if anything, can be interpreted as a immersion-breaking experience.
Imo, reasonable adjustments could be made to make navigating a large cap in a asteroid/debris field more "realistic", without breaking balance. Like adjustment Jinx alluded to.