Biden changed his position because he had to. His administration has no interest in the truth about the lab, or in holding China accountable for its covert gain of function research into bioweapons that appears to be the root of this.
Evidentiary point of fact - he has been in office for almost 6 months with a nary a mention of the Wuhan lab but for a few haggling conservative journalists. There has been plenty of smoking gun level evidence circulating for some time.
I think Josh Rogin leading the charge in the Washpo helped get this issue over the line - he could not be ignored much longer. Prior to Rogin's interest, this was still relegated to conspiracy theory status by the mainstream media. I wonder why?
https://twitter.com/DrewHolden360/status/1397334751774658562?s=20
I have to say, even in the China watcher community, without naming names, people have been scared to analyze this issue. Is that because we know it will represent a permanent, fundamental break with the CCP and the West?
If that scares people away from analyzing it as journalists or interested citizens they need to look inward and ask why. I for one hope the West finally sees the CCP for the monstrous mafia organization they are.