Oh, was this because of limited processing power / slow secondary storage read speeds?

All of that and more. They didn’t have mass memory, so you had a maximum number of contacts, a maximum number of SMS, a maximum number of ringtones… but you couldn’t delete ringtones to make room for SMSses or such. They were a completely different tech.

NO WAY… Oof that must’ve been so annoying, no? Ur phone being a waking advertisement to everyone around you?

They loved it. Also it couldn’t share media (messaging apps didn’t exist yet and it didn’t support MMS) and was GSM only, so to actually do anything smart it had to be connected to WiFi.