Or HaChaim on Numbers 24:19/אור החיים על במדבר כ״ד:י״ט

1 וירד מיעקב, "and someone from Jacob will exercise dominion, etc." According to Rabbi Abraham ibn Ezra Bileam referred to Yoav, David's commander-in-chief. Rashi understands the verse as a reference to King Messiah. I believe that Rashi is correct. If Ibn Ezra had been correct this verse should have preceded the verse predicting the downfall of Edom, as the wars under the leadership of David and Yoav against Moav certainly preceded the downfall of Edom. Edom's downfall is always equated with ushering in the age of the Messiah. Rashi's explanation means that although Bileam had already described the defeat of all the descendants of Sheth, i.e. of all mankind, he wants to tell us that Bileam here gives notice that there will be numerous survivors of the war against Edom and the descendants of Sheth. However, none of these survivors will ever again establish an independent state as previously but they will be ruled over by Jacob.

2והאביד שריד מעיר, "and shall destroy the remnants of the city." Bileam means that not only will these nations not again attain the degree of independent statehood presided over by a king, but they will not even attain enough independence that would warrant their appointing a שריד, a governor of sorts.