It's not really digging into his past. Baddiel has been a public figure in the UK for ~30 years. The Jason Lee incident was on a Friday night TV program about football, in England, at the time when people are coming home from the pub. IOW, it had a large audience - only 4 channels in those days, and no internet or anything.

I have not seen the documentary or read the book, but I did listen to a long form podcast he was interviewed on about the book. His points about the treatment of Jews in modern UK are not wrong, 100% agree from me. However, the Jason Lee thing, and where he said he and his daughter looked like gypsies etc are along exactly the same lines he rightly complains about the treatment of Jewish people.

See:

https://www.youtube.com/watch?v=73427jCig-0

https://www.youtube.com/watch?v=BhHq4m_Bi5g

The hypocrisy should be pointed out even if there are apologies.