The following sutta AN 5.191 is a bit unusual, because it seems to highlight the moral decadence of newer generations of brahmins / brahmans, compared to the older generations.
However, to my understanding, the Buddha was not concerned with intercaste marriages firstly. Secondly, I don't think there was sex slave trade in ancient India. Thirdly, brahmins who were not monks, need not collect almsfood, because they can store and cook their own food. Fourthly, it looks like an ad hominem attack.
So, to me, this looks like a polemical sutta that was inserted later, and not originally spoken by the Buddha.
Was there any commentaries or scholarly opinions on this topic?
Or is this sutta indeed coherent with the rest of the Buddha's teachings?
“Monks, these five ancient brahmanical traditions are now observed among dogs but not among brahmans. Which five?
“In the past, brahman males mated only with brahman females and not with non-brahman females. At present, brahman males mate with brahman females and with non-brahman females. At present, male dogs mate only with female dogs and not with female non-dogs. This is the first ancient brahmanical tradition that is now observed among dogs but not among brahmans.
“In the past, brahman males mated with brahman females only in-season and not out-of-season. At present, brahman males mate with brahman females in-season and out-of-season. At present, male dogs mate with female dogs only in-season and not out-of-season. This is the second ancient brahmanical tradition that is now observed among dogs but not among brahmans.
“In the past, brahman males did not buy or sell brahman females, but took up cohabitation for the sake of reproduction simply through mutual attraction. At present, brahman males buy and sell brahman females, and take up cohabitation for the sake of reproduction simply through mutual attraction. At present, male dogs do not buy or sell female dogs, but take up cohabitation for the sake of reproduction simply through mutual attraction. This is the third ancient brahmanical tradition that is now observed among dogs but not among brahmans.
“In the past, brahmans did not make a stash of wealth, grain, silver, or gold. At present, brahmans make stashes of wealth, grain, silver, & gold. At present, dogs do not make a stash of wealth, grain, silver, or gold. This is the fourth ancient brahmanical tradition that is now observed among dogs but not among brahmans.
“In the past, brahmans searched for alms for their morning meal in the morning, and for their evening meal in the evening. At present, brahmans, having eaten as much as they like, swelling their bellies, leave taking the leftovers. At present, dogs search for alms for their morning meal in the morning, and for their evening meal in the evening. This is the fifth ancient brahmanical tradition that is now observed among dogs but not among brahmans.
“These, monks, are the five ancient brahmanical traditions that are now observed among dogs but not among brahmans.”