I do have a newborn son, which is why videos and pictures are uploaded to Dropbox automatically and then automatically transfered to our private online gallery ... Still no need for massive storage. Would never use my phone as sole location for precious pictures like that.
What happens when you are not near wifi? My Note 4 shoots 2160P at 30fps. That will fill up space FAST. You have a phone with 16gb internal storage, most of that is taken up with the OS, music, apps etc. What happens when you run out of space on the road?
I never said I use the phone or SD card as the sole location, but when I'm on the road and have no access to wifi it IS the solo location temporarily. There are definitely still needs for external storage IMO, at least for my needs there are.