How do unitarity and locality break in theories involing gravity?

In the science-pop article A Jewel at the Heart of Quantum Physics https://www.quantamagazine.org/physicists-discover-geometry-underlying-particle-physics-20130917/, there is a footnote, with the following claims:

Locality and unitarity are the central pillars of quantum field
theory, but as the following thought experiments show, both break down
in certain situations involving gravity.

1. Breaking of locality:

Locality says that particles interact at points in space-time. But
suppose you want to inspect space-time very closely. Probing smaller
and smaller distance scales requires ever higher energies, but at a
certain scale, called the Planck length, the picture gets blurry: So
much energy must be concentrated into such a small region that the
energy collapses the region into a black hole, making it impossible to
inspect.

2. Breaking of unitarity:

Unitarity says the quantum mechanical probabilities of all possible
outcomes of a particle interaction must sum to one. To prove it, one
would have to observe the same interaction over and over and count the
frequencies of the different outcomes. Doing this to perfect accuracy
would require an infinite number of observations using an infinitely
large measuring apparatus, but the latter would again cause
gravitational collapse into a black hole.

In the graviational theories the notion of locality seems to be obscured, because due to the ability to perform diffeomophisms the position is not an invariant notion. From this paragraph, I would think, that it is meant something like $Delta E cdotDelta t sim hbar$, and we take the scale to be $M_{pl}$ – but in the ordinary QFT we have the same uncertainty principle, derived from quantum mechanics.

And the second statement I do not really understand. In the quantum mechanics we assume, that our evolution is governed by a unitary opertator of form $e^{i H t}$, where $H$ is a hamiltonian – some hermitian operator. In the theories with gravity, because of the time reparametrisation, the notion of Energy and Hamiltonian also becomes more subtle, but how to connect it with the statement in the paragraph?

I would strongly appreciate if someone shed light on this statements