We are talking about a 16x difference in resources. Would you also suggest scaling a database that was more read heavy than write heavy instead of splitting reads and writes when you can deal with eventual consistency and just autoscale the read replicas?
The database is the same but you have to then separate your code into reader and writer services with different connection strings, you have to make sure that anything that can’t be eventually consistent uses the writer connection string, etc.
It’s not just a matter of spinning up a database.
Also, since many enterprise apps live stores procedures and putting business logic in the database, that’s another ball of wax you have to untangle.