I don't think we would risk cruising on a line right now that required testing at the port. We're quite comfortable with a required test 24 hours prior to boarding as it allows us to test before we leave home. At least if we test positive then, we haven't already been in a crowded airport, flown on a plane, stayed at a hotel, waited in a busy cruise terminal, and possibly infected even more people. It also negates the anxiety of planning for a possible quarantine, missing work, whatever. We're vaxxed and boosted, along with the vast majority of those getting on a cruise ship - in the overall numbers of positive cases onboard, I don't know if testing 24 hours prior vs. testing at the port makes a huge difference. So I'd rather take the less stressful route of having it done before I got there.
Not saying either choice is wrong or right, it's just preference and personal level of comfort.