Are things forbidden due to the prohibition itself, or due to the reason for the prohibition, and can this be applied to all issues of prohibition?

Analysis and prohibition are the exclusive right of Allah Almighty. What His Messenger prohibited is like what Allah prohibited. The believer must avoid prohibitions, whether he knows their reason or not, with certainty that the Sharia only prohibits what contains pure or predominant corruption. Knowing the reason benefits the mujtahid in performing legal analogy. Sitting in a bar is forbidden for other reasons, including condoning evil, weakening religious deterrence, and that repeated looking at something breaks the psychological barrier, and falls under the meaning of the hadith: "Like a shepherd around a sanctuary, he is likely to fall into it." And what the Lawgiver has prohibited, every means leading to it becomes forbidden, just as condoning evil and remaining silent about it are forbidden.