When was the last time Nintendo had the most powerful console? 20 years ago.
Difference in power is not the reason for the non-reveal.
It's pretty clear - given all the comments from Ubisoft and other devs - that NX is not going to compete with PS4 or XB1. Therefore, price difference really isn't a big deal.
The reason or reasons for not revealing NX has probably got to do with them wanting to not let the hype die. Not to mention that people are already used to short waiting periods between announcement and release date.
It could be that Nintendo wants to not interfere with the holiday period, which normally sees sales increase already in October, if i'm not mistaken (with the actual reveal coming after the holidays).
They still want to sell Wii Us and 3DSs!
What i do fear is that this small gap between reveal and release means that 3rd parties aren't on board again.
What i mean is that i'm having a hard time seeing 3rd parties agreeing to having so little time to promote their games. With all the rush that is coming soon due to the holiday period, they will focus their dollars and time on the games that are indeed coming out soon, not games coming out in 4/5 months (if the reveal was even this month of October).
Can you imagine how NX's launch line-up would be if that happens?
