we have a pretty intensively used postgres backed app handling thousands of users concurrently. After 6 years and thousands of paying custoners, we are only now approaching to the limits of what it can support on the horizon. TLDR: when you get there, you can hire some people to help you break things off as needed. if you're still trying to prove your business model and carve yoruself a segment of the market, just use postgres
Thanks for sharing! Big part of the reason why I decided on postgres, everything I've read about people using it in prod tells me that most organizations never really grow beyond requiring anything more than what it offers.