I've been looking at blogs wrong this entire time
No, seriously. Of course posts are just going to pile up if I treat them as stand-alone and largely unchanging. And post summaries become baggage once they slide off the front page. As for archives, they just tend to grow forever: a different kind of pile-up.
The post should be the summary. Any details should be relegated to a more permanent page linked from the blog: a corner of your digital garden, that you can tend at leisure over time. That is how you reconcile the timely and the perennial, not by forcing wikis to double as blogs or other “clever” schemes.