Yes, third party app stores were a pain for a long time, until Google allowed other stores to update apps unattended. A user having to comfirm each individual update was a terrible user experience.

Google and other pre-installed app stores circumvented the issue by being installed with system privileges to install any app unattended.

Any third-party store who’d want to do the same would either have to pay other manufacturers to be pre-installed, or require their users to root their phone. Or they were annoyed by updates and use the Play Store instead.