Cool! Now maybe put yourself in someone else’s shoes. Someone who doesn’t want to pay an extra $500 for $30 worth of extra storage.
Or someone’s shoes who use their phone for a lot of recording, so maybe they need a terabyte, or more. And those phones don’t exist.
Or someone’s shoes who are offline for weeks at a time and want to load their phone up with movies or tv shows to watch.
Or someone’s who doesn’t use music streaming services so wants to keep all their music on their phone.
There are many cases in which sd cards are useful or even necessary, so try not to think your use case is universal. It comes across as ignorant
I’ll sail the high seas