Respectfully, your opinions are about 3 months out of date. Astra and Opus 5.5 are really a big step up, and most of the decisions they make are reasonable. They also ask you for decisions quite well.
And you don't really need a "spec". You need to describe in detail what you want, but the flow is more like "I want to make a customer forum. The only supported login email should be a magic email link. Write the server in Go using it's html templating. Keep the CSS simple and only use dependencies when it makes sense. Come up with a plan and let me review it."
Then you just review it, a few more rounds of testing, and boom, job done.
You don't really need to be a skilled programmer to do that.