To anyone surprised at this: welcome to the fediverse, please treat everyhing you do or say as public.
The way to achieve privacy around here is by following the long forgotten arts of the old internet before Facebook was a thing: use a Nick name and don’t tell strangers on the internet your real identity.
Your home instance will act as a proxy and only they have access to your email and IP address. That does stay private.
So, as long as you trust your home instance to not leak or disclose your connection or sign up data (which would be illegal in EU countries), just sign up with an alias.
A very positive aspects of this is that it should allow us to detect voting manipulation by correlating the activity of certain potentially malicious actors. If Lemmy instances take vote manipulation seriously and do their best to block bots this has the chance to make Lemmy / Kbin much more transparent and credible than Reddit ever was.