I assume someone is running the numbers for fuel cost and time to just sail around South America, it has to break even or be a better deal at some point.
No big deal.
[1]: Assumes turning around on the Pacific side
[2]: Southbound https://www.searates.com/reference/portdistance/?B=23078&E=2...
[3]: Northbound https://www.searates.com/reference/portdistance/?B=20155&E=2...
You have to get to about 57º to pass around the Horn in open water.
ETA: The southern 40s are known as the roaring 40s: https://en.wikipedia.org/wiki/Roaring_Forties There's not much land to stop the winds from ripping around the planet.
What I'm trying to get at is that, unless the canal was shut down completely for months at a time, there is no economical situation where it would make sense to round the cape instead of just waiting it out.