there are still evolutionary justifications which I'm sympathetic to now and then, but mostly not. In many (most?) cases, understanding if something should be

there are still evolutionary justifications which I'm sympathetic to now and then, but mostly not. In many (most?) cases, understanding if something should be one-one or one-many is known up front. Or should be known. We have decades of examples of best practices with many common data structures. Hard coding a customer account to only ever have one address, for example - no. I don't buy that justification - a customer/address thing - for any size company/project - should just be modeled as one-many (at least). It may be slightly more 'work' up front, but that work avoids potentially major breaking changes and work later on. I get countered with "YAGNI" now and then, but after 25+ years of doing this (and, again, decades of examples of your exact use cases already in google ready to learn from), I can usually tell when you ARE going to need it.