Well myself and several other people on my server finished 180 the day it came out, so I guess as fast as we possible could. For our server that was day 289. Newer servers actually have and advantage in this regard because I doubt my server was the only one to have people fini* first day.

To beat that exam you need to be 53-54k power with 0 nerfs from previous people that beated it (because you absolutely need that very minimum level of power to beat exam 140 and if you don't beat 140 you don't beat neither 180) and you need kurenai, iruka and lee eight inner gates to do it at that power (that even if you are a whale is not said you own them) so there's this unique limitation in time for it to be done (or you need to reach around 70k power and go through it with mb blitz team with an high streak of crits).

On my server guy who is 60k power finish the 180 ninja exam and i think our server have 120-150 day and yes he is full f2p :)

i finished 125, 103 days from opening, and i cleared 150-180 in one day with is the 131st day of opening

53k power will make 179 a living nightmare. 55k is far more doable though.

yep, but you can still do it with enough lucky rolls, in the sense that once in 1000 tries you happen to win, but without kurenai, lee eight inner gates and iruka there's no level of luck that makes you beat exam 140 at around that power :-)