We're in dangerous times in the US, caught between the opposing threats of:
letting a potentially criminal former executive get away with a plot to overthrow democracy (and perhaps conspiring to still do so) and
a current executive politically targeting his predecessor and former - and perhaps prospective - opponent.
I don't trust the FBI, either to be honest and lawful or to avoid botching this through misjudgement, which will strengthen the appearance of alternative 2.
Ultimately this is on Trump and his followers. Without his lies and conspiracy theorizing, their gullible belief, and the attack on the capitol, there could be no suspicion of need for a search of the ex-president's home, as there never has been before.
But make no mistake. Whatever may be found, whatever evidence of crime, Trump's supporters will continue to dismiss it and treat this as merely a banana republic action (alternative 1) that undermines democracy, and Trump will gleefully wave that banner for his own benefit.
Only if there is evidence so strong that his supporters are truly marginalized can we avoid this risk.