First, it's bottleneck (taken from the narrowing of the neck of a bottle). Second, that doesn't solve anything. The problems in the area would still be there. The problems are much greater that a narrow strait or a canal. Sure ships would be diverted away from the strait, but only so long as the politics with UAE remains in our favor.

The problem lies between two competing factions within Islam to begin with. UAE and Suadi Arabis are both sunni and loose allies. Iran across the strait is Shia. They historically and traditionally do not get along. Given the depth of their animas toward one another this would result increased conflict between the counties in the area.

Throw in the meddling by western nations, including are own meddling in the affairs in the area. IMO a canal will not solve anything, just complicate the political situation in the area.