I do not understand your position. I think it's a bit confused.
>The Pareto principle is not some guarantee applicable to everything and anything
Yes, obviously. The author doesn't say otherwise. There are obviously many ways of distributing things.
>One can see how irrelevant its invocation is if we reverse: does Kafka also handle 80% of what Postgres does with 20% the effort?
No
>If not, what makes Postgres especially the "Pareto 80%" one in this comparison?
Because its simpler.
What implies everything can handle 80% of use cases with 20% of effort? It's like saying:
If normal distributions are real, and human height is normally distributed, then why isnt personal wealth? They are just different distributions.
>I do not understand your position.
Let me explain then...
> Yes, obviously. The author doesn't say otherwise.
Someone doesn't need to spell something out explicitly to imply it, or to fall to the kind of mistake I described.
While the author might not say otherwise, they do invoke the Pareto principle out of context, as if it's some readily applicable theorem.
>>If not, what makes Postgres especially the "Pareto 80%" one in this comparison? > Because its simpler.
Something being simpler than another thing doesn't make it a Pareto "80%" thing.
Yeah, I know you don't say this is always the case explicitly. But, like with the OP, your answer uses this as if it's an argument in favor of smething being the "Pareto 80%" thing.
It just makes it simpler. In the initial Pareto formulation is was about wealth accumulation even, which has nothing to do with simplicity or features or even with comparing different classes of things (both sides referred to the same thing, people. Specifically about 20% of the population owning 80% of the land).
Where do they imply the Pareto principle is the only type of distribution?
The author's claim is that postgres handles 80% of the use cases with 20% of the effort. It does not follow, as you recognize, that therefor EVERYTHING handles 80% of the uses cases with 20% of the effort. Where does the author imply that it does? Based on his characterization of Kafka I think he's say it solves a minority of use cases with a lot more effort.
I mean isnt this the explicitly made point by the author? That Kafka's use-case/effort distribution is different (worse)?