

The Encyclopedia Britannica has a great article covering this exact question:
https://www.britannica.com/place/Strait-of-Hormuz
Long story short, the strait is not just the only access point to Kuwait, but also a chokepoint to almost all of Iran, Iraq, Qatar, Saudi Arabia, the UAE and so on.
There is of course the Red Sea, that too allows sea access to some of the countries mentioned above, but that features its own chokepoint strait, the Bab el-Mandeb Strait. That strait is already a conflict zone because of the Houthi conflict. It’s also closer to Israel, and it’s partly under Iran’s control too.
And there’s too little infrastructure on that side to divert enough oil from the countries in question compared to the Hormuz side.

To be fair, there’s the Red Sea on the other side, that connects a lot of the oil-producing countries to the sea too.