Accelerated Database Recovery (ADR) is on by default in Azure and an option in SQL Server 2019. It has some really interesting potential.
I have experimented by turning ADR on in a static test database, and if nothing happens there is no growth. It seems like growth is only going to occur on an active database. So unless you have a test system that allows you to full reproduce your production workload, you are going to be doing your growth experiments in production.
Add to this, turning ADR on or off essentially requires a down time as there is an "exclusive lock" requirement to change the state, and you have a recipe for a career changing event.
If you have a 10GB, database with 50GB available, probably not a big concern. But if you have a 3.5TB database and only 4TB of space available, this could be a big problem.
From the Manage accelerated database recovery documentation:
PVS is considered large if it's significantly larger than baseline or if it is close to 50% of the size of the database.
How can I accurately estimate the growth of using ADR, prior to implementing?