The scrappers in Ghent have done well out of the French Navy in recent years.

Because it took a long time to realize that the old hulls were starting to take up space in military ports.
Then, it was necessary to find an "ethical" solution to demolish these ships, France having abandoned oceanization at sea, and also refusing to send to demolish its warships in India or in Bangladesh to avoid the worries like those related to the departure from Clémenceau to Alang in India.
And these are ships where there is a lot of asbestos they must now be demolished by specialized shipyards.
All this took too much time! ...

It has a little heel on starboard because of a small ballasting problem which was quickly resolved before emptying the dry dock.

Why did it take them 20 yrs to scrap her?

She was decommissioned 20 years ago and, like other former french navy ships left to rot until being scrapped like the Colbert http://www.shipspotting.com/gallery/photo.php?lid=2472821#comments

Looks like it's been lying on the seabed