I am not really a fan of Ti-ko-liōng's comedy. My memory of him largely consists of his ads for his club shows between the innings when I used to listen to baseball games on the radio as a kid.
However, I think saying that Ti-ko-liōng is one of the main factors for Taigi to be considered as crass is like victim blaming. It was the KMT dictatorship and its followers that tried to paint Taigi as crass, in order to dislodge Taigi as the lingua franca. They also helped their cause by killing most Taigi speaking elites during the 228 incident and subsequent white terror.
Sure a lot of Ti-ko-liōng's contents were crass. He objectified women, many of his jokes were sexual harassments. However, that was back when even Taigi opera (kua-á-hì) and Puppet shows (pòo-tē-hì) were considered crass. When a form of Taigi entertainment became too popular, the KMT will shut it down. That included Taigi movies, once much more popular than any Mandarin movies, and televised puppet shows.
At the same time Taiwanese were kept from all public jobs, including teaching, public official jobs. All the society's resources were controlled by the KMT, meaning it's also hard for Taiwanese to be entrepreneurs and start businesses. A lot of frustrations of the Taigi speaking public did not have an outlet. Many people couldn't even diss the dictatorship in the private of their homes, in fear of their children repeating what they said in schools. During the white terror era, you say the wrong things, the KMT would be coming for you. So people more or less gave up on their aspirations and indulge themselves with whatever money they've got. That gave crass shows an opportunity to take hold.
In an environment simply hostile to Taigi, Ti-ko-liōng's crassness basically kept transmission of Taigi through entertainment under KMT's radar, and kept it alive. It was essentially the only form of Taigi entertainment allowed. Many Taiwanese born in the the 70s or early 80s would say their interest in learning Taigi were kept alive because of Ti-ko-liōng's shows.
Despite his crassness, Ti-ko-liōng wasn't oblivious to that fact. He deliberately worked in a lot of traditional Taigi art into his shows. That included traditional folk songs, old location names, differences of Taigi between regions, and old Taiwanese customs. Many Taigi singers also only had his club shows as a performance outlet.