Trump was raided because he continually stonewalled, ignored subpoenas, shuffled documents from place to place to hide them, and just generally lied his ass off. It's even doubtful he actually declassified any.
TRUMP HAD CLASSIFIED DOCUMENTS WHICH HE AS PRESIDENT DECLASSIFIED WHICH IS LEGAL. YET HIS HOME WAS RAIDED BY THE FBI. BIDEN HAD CLASSIFIED DOCUMENTS IN AT LEAST TWO LOCATIONS WHICH HE DIDN'T HAVE AUTHORIZATION FOR; SO WHERE'S HIS FBI RAID?