Quite an emotional subject, and nobody likes to see a once proud warship in the knackers yard; but, this happens to 99.9% of ships. The only argument is whether keeping the Invincible (and the Ak Royal) in service would be viable and economic. The alternative (in the Libyan war) of staging RAF warplanes from Southern Italy has proven both extremely expensive and limiting in operational terms, compared to keeping just one of the Invicibles in service with remaining Harriers off the Libyan coast.
This rational and thoughtful post is insufficiently vitriolic and frothing and has no place here.
Nearly all warships go to breakers at the end of their lives, even those that gave proud service for many years. There frankly isn't enough dock space in the world to make a museum ship out of every worthy candidate, and if we were to do so, the lack of visitors to any given ship would put them in a state quite more pathetic than proud and shiny razor blades. This is how the world works.
Plus, people forget that the history of the RN is literally over half a millennia old, and ships come and go. They scrapped Warspite, after all, and it's honestly somewhat of a wonder they kept Belfast at all.
The way I look at it, the RN doesn't see a pressing need to preserve warships because they live on more than well enough in tradition.