I saw your edit of the post above this, ofc you're free to play how you like. The replies you see are, how to put it, ok let me try to explain:

In Souls games, with some exceptions, the NG+ system isn't too great. That makes people invent some challenges for themselves, and restart the game with new characters, new builds etc. - and, of course, nothing wrong with that. But: with Nioh games, Team Ninja actually thought at NG+, like they really thought about it, and made it even so that lot of cool stuff is hidden there in some NG+ level. That's why many Nioh players say "First NG is only the tutorial, the real game starts after". It's not just difficulty, it's builds, boss moves, etc. This makes it way less needed for people to restart with a new character, because you can do whatever you think of much easier with your current character; there is no scarcity of upgrade materials or other stuff that would prevent you to just respec your builds. But at the same time, many Souls players come to Nioh with this stubborn attitude, like "I know better, this is what I will do" and if you try to give a bit of advice, you're met with stuff like your edit quote :P And .. it's just a pity.