Flatly, yes. And she wasn't 47% before the buff. She was already a shade off 50%, even in the jungle which was already statistically her strongest win% role. She's been steadily climbing over the past few months as other champs are nerfed around her.
A mechanically complex champion getting these sorts of win rates results is smoke to a fire; the supposed high skill floor is being overwhelmed by the numbers in the kit and for Nidalee that's evident with a quick glance at her numbers. Correlation isn't causation, but the moment the likes of Zed, Gnar, Elise, old Nidalee sniffed 50% win rate they became permabanned. An interesting recent example of this trend is Jayce. Started off S4 with a ~47% win rate and due to the nerfs to other champions throughout the season he was a hair shy off of 50% by the time Worlds rolled around and like clockwork he shows up in competitive again. More recently you can see the same thing with Kalista; gets to 50% win rate and immediately sees competitive play and bans.
(For the record I'm actually thinking of trying Nidalee out soon. I'm always in the market for a jungler who can lane as well)
I think I'd go quite a bit further myself...
I'm not sure where you are grabbing your win percentages, but looking at lolking ranked solo, she's been steady between 46 and 47% winrate up until the jungle change patch where she jumped to 50% immediately.
As far as skillcap, she is up around 53-54% in diamond. So that's about the cap I'd put her at. That is high for a champ but compare that to the top 20 or so champs that have that kind of winrate across all tiers it doesn't strike me as overly OP. If we balanced everything about the top 2% of players then we'd be in trouble. If she comes out in competitive and starts looking ridiculous, I think you'd see an immediate change. Pantheon for example was WAY stronger than Nidalee and still didn't see any changes for awhile.
I'd believe there is an issue with her general kit strength if she was higher winrate before the jungle change. But frankly you didn't see her much. Sure her spears can chunk someone but that takes quite a bit of AP to do so (I don't really think a single anecdotal complaint warrants a nerf). The top mages are FAR worse in the midlane and I don't even think she rates in top lane anymore. Her pick rate has been 10% or less pretty much all along. She's got her fans. Always has.
I'd say try her out. She's fun, mobile and can be a threat but not a huge damage dealer unless you're building her as such. Base numbers aren't super great. Huge damage threat built AP but pretty squishy.
I've faced her a few times as well. I had no issues dealing with her as Sejuani. Even had an OK time as Vi.
Other than being fun and myself enjoying mechanically challenging champs, I still don't think she's better than the tier 1 junglers (Jarvan, Lee sin, Vi, etc) nor do I think she's as good or better than the top midlaners (Cassio, Ahri, Katarina).
Any nerfs might just knock her completely out of viability for laning. Which might be ok. Who knows.
I just don't see her as even worth a ban right now. Definitely not in gold. Maybe higher she might be.
She probably will get tweaked some. Not sure where it'll be though. I'd start with the neutral monster stun. Maybe lower her AP ratio on the spear.
I know them feelz bro.
