It's not clear that the aggregate work is allowed to be distributed under the GPL. My legal hypothesis (from having worked with BSD licensed code and noticed how much hassle having many licenses is) is that the extra requirement of repeating the MIT license could be challenged against the "extra restrictions" clause of the GPL. Think of the case of having 500 variant MIT/BSD3-clause/et licenses that CLAIM to mean the same thing and need full reproduction; the cost of having lawyers verify this is substantial, so it is an actual substantial restriction.
GNU believes that the lax licenses (MIT, advertising clause free BSD) are "compatible with GPL" because the GPL requires attribution and the licenses can be considered a form of attribution.
The actual status of this has, to the best of my knowledge, not been tested in court. Because this is a claim from the group that wants to add restrictions (the GPL side) and they generally want to be able to take BSD code and apply extra restrictions to it, it's not clear it's a large risk in practice.
GNU believes that the lax licenses (MIT, advertising clause free BSD) are "compatible with GPL" because the GPL requires attribution and the licenses can be considered a form of attribution.
The actual status of this has, to the best of my knowledge, not been tested in court. Because this is a claim from the group that wants to add restrictions (the GPL side) and they generally want to be able to take BSD code and apply extra restrictions to it, it's not clear it's a large risk in practice.