The most likely solution to the Fermi paradox is either that abiogenesis is very hard/rare (which is heavily supported by the staggering complexity of the simplest molecule that can reliably self-replicate) or that technological intelligence is very hard to evolve.
Or terraforming is a hell of a difficult task and these civilizations didn't manage.
Or they colonised our galaxy, but our biosphere was toxic to them so they skipped it because sterilizing a planet was immensely more difficult than terraforming one.
Or our biosphere was toxic to them and they died.
Or they sterilised every place they found, so only those who didn't encounter them survived.
Or they had ethical concerns regarding coming here.
Or they prefer red dwarves because of their longer life.
Or they prefer O'Neill colonies around rogue gas giants where they harvest fuel for fusion.
Or they calculated a more efficient way for survival.
Or the time scales for galactic colonisation are largely exaggerated.
Or the development always needs a few billion years at least, and we are one of the first.
Or their planets became uninhabitable before they reached space.
Or Congress never got to approving the funds for an interstellar mission.
Or they waited too long and their civilizations went into a decline.
Or they actually have a subsurface civilization on Mercury and Enceladus right now.
Or all of the above.
I fail to see how can something be a paradox when it relies on too many assumptions in the first place.