My issue with the iPad is that it just does not have the fine-fidelity or response time of real ink, and it's not something that never fails.
It's so frustrating to be so pregnant with an idea, to open ones iPad, and to find out the battery is low, Procreate isn't working, the Notes app is confusing to navigate, oh no you're writing but your palm has slid on the screen, etc.
I've spent a lot of time searching for a digital alternative, but IMO we're at least a decade away from digital handwriting being even close to on-par with paper, even ignoring friction and feel.
I do find the iPad battery drain to be annoying and inexplicable. When they first came out, iPads held a charge for weeks in standby. New ones drain in a few days, even when background app activity and such are disabled. And you're right that it is frustrating to pick up your iPad and discover that the battery is near-dead, which happens with surprising frequency.
That critique doesn't apply to Remarkables or Kindle Scribes though.
I agree. My iPad 2 could last a month or more in standby. My iPad 8 maybe one to two weeks.