Well, as a newbie by myself some weeks ago, i have to disagree. The experience of the game would have been really watered down by a strict separation of new and experienced players. During my travels i encountered more and less shady sailors and many helpful seafarers, discussed the possibility to join a clan, got intercepted by a lucky pirate, who found a sealed bottle in my cargo hold (was a nice chat afterwards) and always found room and freedom to experiment with ships, tactics and - most important - adventures!
Show me a more thrilling event, than to sneak as smuggler with your first self-build Trader Lynx into the harbour of Mortimer Town ;-) I didn't succeed, abd not because of the veterans. It were the other newbies with their basic cutters, and it was a really great hunt! :-) And all happened with several 4th and 5th grades in sight. Or my try to smuggle a trader lynx full of compass wood from an enemy harbour to a high price selling market during the latest French-Spanish-Dutch war actions during server primetime - it was all of my meager wealth into this small ship and i sweat through all of my shirt during the journey.
I had until now a handful of encounters with raiding squadrons (i dont't like the term "gank") and most of time, i got away. The cargo and ships i lost were caculated risk and mostly lost by my own bravado. But without the constant threat (= thrill) of pirates and hostile raiding parties all of the game would be only half or less exciting than it is. Especially as newbie!