Maybe this will unconfuse: It doesn't matter as long as you can scale with your operation both in capacity and financially. That means that if you decide to use AWS, Google cloud, Azure, Oracle Cloud (hihi) or bare metal on Hetzner, you need to start small to handle the initial capacity and then some. But you also need to make sure that you can scale up or sideways, and that you plan and know how this will work and how much it will cost. Then your infra growth is tied in to your revenue. More users == more money == more infra.
And because you asked, I've used AWS, Google Cloud, Azure, Oracle Cloud (hihi) and Bare Metal (but not on Hetzner). All for different projects, different requirements etc. And all followed that rule - Grow with your actual growth/revenue.
