The last 'troublesome one' they actually got rid of was Charles I (not suggesting such drastic measures even for Andrew).
Edward VIII still had to abdicate, whatever might have happened behind the scenes to bring that about.
The point is that the hereditary system is inherently flawed. I very much doubt even the most ardent royalist would consider Andrew to be a fit person to be king, yet, the system that would put Andrew on the throne (or require an abdication) is the system that has put Charles there and will put William and George there.
Once you start arguing that this potential king or that potential king can and should be removed from the line of succession, the whole thing crumbles - it's either a meritocracy or it's not.
If Andrew can and should be removed - consider Charles. Not a terrible person but certainly a man who has made many mistakes - there are people, mainly fans of the late Diana, who believe the throne should have passed straight to William as a result of Charles's conduct - so where does it end?
Being a royalist means you accept whoever is next in line and I'm afraid you can't weasel out of it with hypotheses about Andrew being forced to abdicate should he have succeeded the late Queen.