4K videos, AAA games, lossless music, things add up quickly and if the result is more gigabytes than you have in your phone, then you have to do the cursed "storage shuffle" dance. Sure, a microSD card slot can tilt things in your favor but those are far less common today than a few years ago. Plus, flash storage prices have been falling recently, so how come there are still plenty of 16GB and 32GB phones around? The worst thing about this is that it's not a one time concern, but instead something to think about each time you upgrade. Each new phone has to have equal more more storage...
Source: https://www.gsmarena.com/weekly_poll_how_much_storage_is_enough-news-28536.php