re: Wonder how many ‘celebrities’ lie about what they really believe?

Not all.

Not a majority.

But probably more than just a few.

The reality is that few Americans think about politics enough to really even know what they think rather than just parroting someone else and/or tribally reacting. And celebrities are no different, and possibly are even more shallow and weak minded than the average American. In Hollywood you are surrounded by the leftist culture (which is why your friend succumbed to it), and there's no reason to think that it doesn't do the same to the celebs. Especially for those in movies, since they usually come from a college theatre background and have already been indoctrinated since they were still teenagers.

All that said, I also have no doubt that for those who do have different views, there is no shortage of leftist willing to blackball/cancel them for those views.