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The tapdancing attempts to get around the Fermi Paradox simply ignore the list of ever-increasing number of factors needed for a planet to sustain intelligent life.

In addition to the obvious life-hospitable factors, such as a temperature suitable for liquid water and a suitably-sized sun, there are many more factors required for a planet to be fit for intelligent life (with more factors likely to be discovered in the future). Some of these are:

Suitable gravity for atmosphere, with appropriate pressure, to retain oxygen and water vapor but not hydrogen; suitable axis rotation rate; appropriate tilt of planet axis for seasons; suitable orbital distance from star to prevent tidal locking and far enough so that solar flares would not strip the atmosphere; magnetic field from planet molten core to shield lower atmosphere from cosmic radiation; sufficient planetary plate tectonics for crustal mineral recycling; suitable distribution and shape of continents to sustain deep ocean currents; sufficient actinide radioisotopes in planet interior for decay heat; suitably-sized moon to create needed tides and stabilize planet rotation; giant outer gas planets to prevent large asteroids and comets from frequent collisions with the Earth-like planet; suburban galaxy location providing sufficient distance from recent supernovas; a special suburban location so that the planet has sufficient phosphorus concentrations; far enough away from gravitational disturbances by higher density of stars in inner area of galaxy; only minor orbital variations caused by small chaotic gravitational interactions between other planets in the solar system.

With these factors the number of planets in our galaxy capable of sustaining intelligent life is much smaller than the media and grant-seeking astronomers imply in their articles. The estimated probable number is likely very close to the experimentally known value of one.