I was with him until his use of Judith Jarvis Thomson's thought experiment to justify stating that the personhood of a fetus is irrelevant in the abortion debate. That thought experiment is only useful in justifying abortion in specific circumstances, such as cases of rape or some other situation where the woman is somehow impregnated without her knowledge or consent. It completely removes the woman's agency from the moral calculus and assumes all women who become pregnant somehow play no active role in the reproductive processes that result in pregnancy, and therefore aren't at least partially responsible for the fetus being in the position of needing to use the woman's body to survive. In order for this thought experiment to justify abortions in all cases you would have to believe consent to sex is not tacit consent to the potential ramifications of sex, which would seem to be a very naive view to have considering how well known, and frequently occurring, the potential ramifications are. This kind of logic could potentially allow you to selectively consent to only the good outcomes of potentially risky behavior, and none of the bad outcomes. For example, you could say that you consent to speeding on the road, but only if it gets you where you want to go faster and not if it gets you a ticket, and definitely not if you accidentally kill someone while speeding. Most people will not find that form of selective consent a compelling argument when it comes to determining whether or not you were at fault.
Now don't get me wrong Ben Shapiro's an idiot, and there are good justifications for abortion, but not ones in which the personhood of a fetus isn't a factor. The debate is definitely about when human life begins, but there's not a definitive answer for that and there likely never will be. The good news is that the people saying that life begins at conception have a really bad argument. If a zygote is a person then a grain of sand is a beach. The problem is determining where between zygote and birth personhood begins. This is where having good arguments and being able to compromise is helpful. Personally, I think the point of higher brain birth (22-24 weeks) is a reasonable point to identify as the likely beginning of personhood, but I've heard all kinds of things argued competently. Regardless, this philosophy tube video makes a bad argument. Having listened to more of it while typing this he has subsequently made the argument that even responsibility for the position the violinist is in should have no bearing on whether or not it is morally permissible to disconnect him from the host and allow him to die. Philosophy tube has now pivoted from arguing that personhood is not a factor, to arguing that even if it were it wouldn't trump the host/woman's right to bodily autonomy. That's an argument, but not one that the aforementioned thought experiment supports.