By being ripped out and sandboxed the same way other apps are, Google services isn’t free to siphon battery. This means you can restrict battery use and cut the constant communication down. Thus saving battery. If you allow it, yes it is not different than if it was preloaded.
Depends on ISP.
If IPv4 ban, it is indeed 100% ineffective. Nearly all ISPs either CGNAT or rotate addresses. If IPv6, the ISP just forwards a 64 bit block and leaves it at that. You must call and request a new IP block. In which case you’ll be told yes or no. If yes, it’s either free or paid.
I know with ATT Fiber, they don’t offer address changes unless there is some security or service interruption reason. You have to unplug the modem for 30+ days so the lease expires if you don’t want to do rounds with support. My IPv4 address has changed once, but my IPv6 address block has never changed.