Philosophy posts are enjoyable if they're interesting. They're useful if they're right.

Philosophy being right isn't enough to make it necessarily useful. There is a potentially unbounded space of philosophical concepts to explore and most of them are not of instrumental use at this particular time. We can't say much more than "They are useful if they are right and they are, well, in some way useful".

(I hesitate before pointing out the other side of the equation where a philosophy can be useful while actually being wrong because in such cases, and when unbounded processing capability is assumed, there is always going to be a 'right' philosophical principle that is at least as useful even if it is more complex, along the lines of randomized algorithms being not-better-than more thought out deterministic ones.)