The strait has been open for weeks for friendly countries' ships that pay Iran $2M per passage through their "toll booth", an unmined route through Iranian territorial waters.
This ceasefire appears legitimize that situation. If it holds, Iran is about to make huge amounts of money on top of sanctions relief.
The threat why boats do not cross are Iranian missiles / drones striking ships attempting to pass thru, without paying a protection fee. It's basically a terrorism protection fee.
For Iran's toll system to work, they would need to strike at ships sailing in Omani territorial waters, which is an act of war.
the alternative is that oman and many others can also do the same thing, and the lot of states interested in trade in the area need to get together an negotiate a setup that everyone can agree to