I've been using PostgreSQL for a decades, and I feel so spoiled. It always Just Works. Not to say there've never been bugs, but compared to anything else with that much surface area, it's a brilliant piece of engineering.
It's astonishing how often it's a perfectly fine stand-in for the "right" solution. Need a K-V store to hold a bunch of JSON docs indexed by UUID? Fine. Want to make an append-only log DB? Why not. Should you do those things? Probably not, but unless you specifically need to architect for global-scale concurrent usage, it's likely to work out just fine.
For me, it's the default place to stick data unless I have a specific requirement that only something else can meet. I've never once regretted using it to launch a production system, and only a couple of times have needed to migrate off of it due to performance demands.
Thanks, PostgreSQL team! You rock.