The grift is a huge part of why this is still going and being supported by so many. That is, the likes of conservative media, high profile conservatives and various Church personalities. But underneath it all, there are definitely people who think Trump won the election, including Trump himself, Giuliani and probably various Qanon idiots. The grift is all of the people attaching themselves to the 'cause' and seeking fame, power and donations off the back of it.
I think Guiliani knows the truth. Given that he's apparently under investigation, I think he's just been digging in so hard for that sweet, sweet, pardon.