It's combat debut was during the Kosovo War, which was clearly _not_ people who are literally living in caves, during which the F-117 suffered its only combat loss, shot down by anti-aircraft missiles, successfully tracked by the radar.
OK, but what's it good for today? Kosovo was 20 years ago. If the B-2's role is to fly conventional missions, the MQ-9 can be armed with the same weapons that the B-2 carries.
Getting inside an integrated air defense network to take out strategic targets. It's got what is believed to be a better stealth profile than the f-22 or f-35, while having payload comparable to a b-52. The MQ-9 wouldn't be able to get anywhere close to an air defense network.
Large scale strikes also, but after air defenses have been taken down, or suppressed by SEAD escorts. Keep in mind we only have 21 B-2s and they are very expensive to maintain, so it makes sense to use the B-52 whenever possible.
