^Yes, Kirk's a famous captain, but he wouldn't be the only famous captain. Heck, when you're exploring the uncharted reaches of the galaxy, it would be hard not to achieve history-making feats.
Besides, just because somebody's famous, that doesn't mean that every single person in the future has studied his career so intimately that they'd immediately know the difference betwen two versions of his ship 20 years apart. I mean, I know about Ferdinand Magellan's historic circumnavigation of the globe, but I couldn't tell you what any of his expedition's ships looked like at any point in their lifespans. I'm not denying that Kirk is a famous historical figure, I'm just rejecting the kneejerk assumption that everyone in the 24th century is a Trekkie who's studied every one of Kirk's adventures as exhaustively as TOS fans have done.
Besides, just because somebody's famous, that doesn't mean that every single person in the future has studied his career so intimately that they'd immediately know the difference betwen two versions of his ship 20 years apart. I mean, I know about Ferdinand Magellan's historic circumnavigation of the globe, but I couldn't tell you what any of his expedition's ships looked like at any point in their lifespans. I'm not denying that Kirk is a famous historical figure, I'm just rejecting the kneejerk assumption that everyone in the 24th century is a Trekkie who's studied every one of Kirk's adventures as exhaustively as TOS fans have done.