The way the clearings work now is that the pets are manually moved to a showroom on another account then deleted. This automation just cuts out the middleman and doesn't change the end result. Leaving the pets on the account leaves an artificially inflated count of the species/colors for users that probably aren't coming back (which for the rarer pets provides a false sense of availability when it isn't really there). For banned accounts, they're definitely not getting the pets back so that's an easy call. For inactive accounts, if you're gone for that long I highly doubt you remember what you had anyway so it probably wouldn't matter too much.
I'm sure OAKs are a unique situation but even those, given the current system, would simply be deleted in a clearing under the right circumstances. If they lose the name, that's because they're either banned (in which case they aren't getting it back anyway) or have lost all interest in the site for a very very long time. I'm sure staff could work with someone directly to put the OAK on another pet of the same species/color as the original if it came down to that, but the name shouldn't be automatically saved forever just because the user got an OAK and then decided to leave forever.
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