One of the last times I saw Walliams on tv was on This Morning, this year, some months back, flogging his book.
They got past the interview, just. However at the end of the show he had to infiltrate the clothing segment, where he came on in some woman's outfit. What made the producers let him do that is known only to them, but they obviously thought it was funny. It really was not funny, it just went to reaffirm that he was an odd character with dubious comedy values.
Wallliams always had to take it to the next level of weird, tv producers just pandered and indulged him with his odd behaviour, all in the name of being 'funny'.