For context, I am mainly talking about my personal projects, ideas I am trying out, MVPs/prototypes for potential new businesses, etc.

I have started just using Postgres to back queues. It is simpler (although I have spun up new apps with Redis so many times it is only a small improvement) but more importantly it is cheaper. I really do try a lot of stuff out, so completely removing a infrastructure piece is a nice money saver. Again, not massive but it's cheaper.

The downsides of doing this in the prototype/MVP context are minimal. At the scale of prototype and MVPs, I certainly don't see any difference in performance.

I did note in the graphic it listed Kafka but in the lower table graphic I did not see any Postgres replacement for Kafka. If I am at the scale where I really want Kafka, it is probably for performance and I just can't believe there's anyway Postgres could provide that.

So, I love the flexibility and all-in-one abilities of Postgres for prototyping and making MVPs. But at my job, nobody is proposing exclusively using Postgres for persistence.