Because the far right-wing members demand it, despite no evidence. Kevin McCarthy needs to appease them to remain speaker, because if he denies it, the knives will come out. And finally, the major reason is to distract people's attention from Trump's massive legal issues while slander Biden despite there being no evidence. And, as many of us have been saying an impeachment was virtually guaranteed when the GOP re-took congress. MTG and Gaetz demand it, Boebert as well. As I said, Biden could cure cancer and they would slam him for hurting the profits of hospitals, doctors and pharma cos...
Also, I think it is hilarious that you think this is some gotcha response. Like, seriously, you think this actually means Biden is a bad President? Trump was impeached twice, both times with loads of evidence....but the GOP were too cowardly to convict.