Old microsoft account

Even if you change information, the birthday of the account stay how it is so it would never be your account.

Be creative and make a better gamertag or restart with a new account.

Change the account information? That's ridiculous. So if Stallion doesn't play for a year you could just take his account and have a huge gamerscore? Why not just free up the gamertag instead? Anyway, like others have said, it's been abused before. Also,
I don't think a year is enough, especially when the tag has been actively played on. Maybe silvers with 0 gamerscore.

They've unlocked them before. I know a few people who took advantage of this. However, I only saw one announcement and the unlocking of old gamertags was very random and sporadic over the course a few months.

[quote user="Matt Kmetz"]I was just wondering if you guess think that we should be able to use gamertags from very old and inactive accounts,[/quote]No.

I would support this, but you can't really tell why someone isn't actively using their account, so in some cases it could be unfair to just deactivate and sell off someones gamertag. They thought of it first, and used it actively at some point, it's theirs.
Now, gamertags that have been squatted on but never used for anything should be cleaned up more often.