Saddly Note 4 is pretty much the last of the user replaceable battery phablets. Which is why I still have mine, and it is on its second battery. I will comfortably STATE that if you want your phone to last 3+ years and you use it heavily and you want the same run time, you NEED to either have a user replaceable battery (and replace it) OR send it in and get the battery swapped.
Sadly, most consumers swap out their phones more frequently and never see the dreaded rolloff in battery capacity. Unless that changes, and I seriously doubt it will, we are stuck with disposable electronics. I, personally, think that is insane with high end phones crossing over the $1000 mark. If the purchase model changed from massive subsidies and multiyear contracts to upfront purchasing, perhaps this would change.