To me, God revealed to Peter by means of a vision that no MAN was unclean. The vision of unclean animals was like a teaching tool for Peter to understand to not call any man unclean - which I base on the following verse.
Acts 10:28 And he said unto them, Ye know how that it is an unlawful thing for a man that is a Jew to keep company, or come unto one of another nation; but God hath shewed me that I should not call any man common or unclean.
Yes the ceremonial and dietary distictions came to an end after Christ's death on the cross..through which those disbarred from access to God are now on a perfect equity with the Jews...
But God would not have told Peter to eat these "unclean" animals if He had not meant it, and had not declared them clean as He said.
Which of course was my original point.