It's very easy to get onto a server, you just have a look in LFG, join their discord and apply, get white listed and get the password, it is simple and doesn't take much time at all.

Thing is, if you actually did that you would understand how poorly the current state of the game is for large scale multiplayer and would likely quit very quickly.

For starters, almost nothing respawns so you need active admins to constantly respawn resources.

The lag is horrible and the constant desynch means your boats take a large amount of damage while sailing them assuming they stay a float, it is not uncommon for boats to capsize due to this desynch issue, I lost 2 long boats in calm waters just outside my base.

Finally, your loot cache can be opened by anyone so if you die, crash or just plain log out, anyone can loot all your stuff.

In summary, good SP and Co-OP game but right now, terrible MP experience.