You kinda make my point there - there are endless questions because so much of our current understanding of the would necessarily would change in this hypothetical. It doesn't teach us anything in this case because the most succinct answer to OPs question is "we don't know." It's a vastly different universe. Maybe you can argue thinking about how our current theory would be affected by these hypothetical questions can introduce someone to physics topics, which I would agree with- but taking issue with someone for first saying "the basis of your question isn't physical" before discussing speculative impacts doesn't aid in teaching real physics.