The Korea Times has an article published that discusses what little options South Korea has to deter North Korea’s trash balloons:
Complicating matters for them is the apparent shift in North Korea’s intentions behind the balloon launches. Initially, Pyongyang claimed the balloons were in retaliation against anti-North Korean leaflets sent by South Korean civic groups, many of which consist of defectors from the North.
“The regime has continued the balloon campaign even after the leaflet launches stopped. This suggests that the balloons are now a tit-for-tat response to South Korea’s use of loudspeakers along the border,” Yang said.
In late July, South Korea resumed propaganda broadcasts across the border in response to the balloon launches. These broadcasts operate simultaneously from fixed loudspeakers in the border regions at full volume.
A military official said that the broadcasts are still operating from 6 a.m. to 10 p.m. but declined to provide further details, citing operational secrecy.
“Instead of blasting the broadcasts day and night, our military should use the broadcasts more flexibly depending on the North’s behavior, such as switching them on only when it launches the balloons and turning them off when it remains silent for days,” Cho said.
Yang suggested that an ideal scenario would be for both Koreas to agree to a moratorium on psychological warfare, although this seems unlikely given their hawkish stances and the absence of a communication channel.
The professor also mentioned the possibility of international organizations such as the International Civil Aviation Organization (ICAO) — where both South and North Korea are member states — mediating to ease tensions caused by the balloons.
He added, “Unless the government takes swift action, we are going to see thousands of more balloons since conditions are becoming more favorable for North Korea’s balloon launches, with winds blowing southward in the fall.”
Korea Times
You can read more at the link, but I don’t think North Korea has any intentions of stopping the trash balloons. It is a low cost gray area provocation for them that is providing them valuable military intelligence on where these balloons are landing while disrupting South Korean society. This disruption is putting pressure from the public on the Yoon administration to do something when there is really not much they can do.