One place bisect shines is when a flaky test snuck in due to some race condition but you can’t figure out what. If you have to run a test 100000 times to be convinced the bug isn’t present, this can be pretty slow. Bisecting makes it practical to narrow in on the faulty commit, and with the right script you can just leave it running in the background for an hour.

We really would benefit from a Bayesian binary search for this purpose, so you can get by with only running the test 1000 times in most cases.