Nothing, other than a certain administration, changed in the meantime. No new evidences. Yet now experts agree it's worth investigating.
I feel you're heavily distorting facts and misrepresenting them disingenuously.
The blend of remarks that you are referring to weren't based on a newly-found passion for the scientific method and objective thinking.
I'm sure you are fully aware that you are referring instead to baseless accusations fueled by conspiracy theories on how the virus was man-made by China in it's lab.
In some cases these conspiracy nuts go to the point of calling the leak intentional and even accusing it of being a bioweapon attack on the west.
There are also those who for some reason insist that Fauci is the mastermind behind the lab leak and not catering to the conspiracy theorist's demands is proof the US government in general and Fauci in particular is behind the virus.
And these accusations are reiterated in spite of any evidence of statement on the behalf of experts clearly refuting the conspiracy theories.
So no, it's disingenuous to frame what has been happening as being evil censorship attacks on honourable truth-seekers who routinely uncover major conspiracies by doing their own research and thinking independently.