It's intentional(mostly to make it more challenging, IIRC). Just enough for the repair truck. AIs are smarter, now(you can't rely on the old "bait 'n drag" AI exploit that let you pretty much dominate 90% of retail MC2 missions, which alone, IMO, is a pretty huge deal), and the game also now supports indirect-firing LRMs at hostile sensor blips, not just at 'Mechs and vehicles currently in LOS of a unit, which means those LRM Carriers can be a threat even when none of their fellow units can see you directly. Ranges are longer, too.
I could probably go on for a while; it is a bit harder, but in many ways, a fresh, yet still familiar experience for those who've played retail MC2.