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The answers I have seen do not take into effect the growth of the radius of the event horizon as significant amounts of matter get close to the existing event horizon. I would have expected that rather than it taking forever to cross a fixed event horizon, reality would be that a growing spherical event horizon would engulf the object falling into the blackhole.

Qmechanic
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Leigh Stevens
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    How is the event horizon supposed to "grow" if nothing ever falls past it? Related/possible duplicates: https://physics.stackexchange.com/q/82678/50583 and its linked questions – ACuriousMind Dec 17 '18 at 23:51
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    This seems to start from a misconception and then propose a way to poke a hole in the misconception, which wasn't valid in the first place. It is not true that matter can't cross the event horizon. See https://physics.stackexchange.com/questions/5031/can-black-holes-form-in-a-finite-amount-of-time –  Dec 18 '18 at 00:25
  • The object is only "frozen" at the horizon in coordinate time. It most definitely crosses the horizon in finite proper time. This is one reason not to entrust physics to a particular coordinate chart. Growth of the event horizon is not usually taken into effect because the Schwartzschild metric does not allow it - it is static! – m4r35n357 Dec 18 '18 at 10:22
  • @ACuriousMind A thin shell of the same mass $M$ as the BH collapses to the EH, but doesn't cross it yet. Would the horizon radius not increase to $2M$? Whether or not you believe that the growing horizon pushes nearby objects off, either way you have to admit that the horizon grows before the infalling matter crosses it. – safesphere Dec 18 '18 at 17:20

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