Is the login oidc and pkce compliant? Does it support SSO? Persistent login? Gdpr? How does account recovery go if Google kills a customer account? Does data get linked to crm? Does it scale horizontally? What database does it use? How does it handle attacks and spam? Does it support images? If so, how do you mitigate CSAM? How do you track usage and engagement? How do you get alerted if your forum is down?
I ask all of this because while AI can build what you describe pretty easily, it's also completely useless from a business perspective. You're right that years ago, you'd have a small team of devs writing this buy something off the shelf.
But when your C-suite hands you the code and tells you to deploy it, what then? Does it even support admin users and mods or is everyone going to Couchbase to edit the tables directly.