In some cases yes you do. It depends on how the account is flagged, I'm not sure what the flag is, but valid links can and do return a 404 if you're not logged

In some cases yes you do. It depends on how the account is flagged, I'm not sure what the flag is, but valid links can and do return a 404 if you're not logged in. You also can't view replies or context for individual tweets, which makes seeing one tweet next to useless.