Daegu Mayor Hong Jun-pyo: ”Recent opinion polls are also artificial... Announcements of responses of less than 15% should be prohibited” (South Korea)

On the 2nd, Daegu Mayor Hong Jun-pyo pointed out the problems with the current opinion poll system, saying, "Results with a response rate of less than 15% should be banned from being published."
On the same day, Mayor Hong took to his Facebook page to talk about the changes in his approval rating when he ran for president, and again commented on the idea that opinion polls are useless.
Mayor Hong said, "During the 2017 impeachment presidential election, my approval rating was always in the single digits, at 7-8%, until one week before the election.
The poll was announced as less than 10% of the total votes, but the then candidates Moon Jae-in and Ahn Cheol-soo were announced with similar figures. This was the most reliable poll in Korea.
"The fact that the organization made such an announcement at the time was not a legitimate opinion poll, but rather an attempt to manipulate public opinion to shape a particular candidate's opinion.
I have seen it. I have seen the same tendency in the opinion polls for this general election, and in recent opinion polls as well. That is why I am raising the issue of the uselessness of opinion polls."
Mayor Hong said, "If the response rate is less than 15%, it should not be published, and so-called corrections should not be made. If the response rate is less than 10%, it is possible to manipulate the polls as much as you want depending on the design."
"This reminds me of a polling agency that suggested at the party conference in July 2011 that if we gave them 300 million won (US$340,800), they would manipulate the votes by 10 percent," he wrote.