I agree that a lot of subscriptions are really overpriced, but updates to an app are also a sort-of service. Pixelmator explained it quite well when their app switched to a subscription model, mentioning some fair (I think) pros and cons of the succession model, both from the perspective of users and developers.

https://www.pixelmator.com/blog/2022/08/18/why-pixelmator-photo-is-switching-to-subscription-pricing-and-a-sneak-peek-at-pixelmator-photo-for-mac/

Autoscaling isn’t only used the grow the number of servers under load, but also to guarantee availability of a fixed number. If the max is set to 1, the bastion host is protected against hardware failure, zone outages, or just you screwing up. Accidentally killed your bastion host? No problem, within a few minutes autoscaling will have provisioned a new one and you’re good to go again.

Arstechnica runs on WordPress on AWS, and they have a really nice series of articles about it. Sure, you could use just one EC2 instance for everything, but on a high traffic website you would need a bit more.