Hi, you could say that, e.g if you had visited a palace and were asked -
‘So, what was the library like?’
‘The room was as splendid as any’
I.e when asked about a less well known room in the palace, you reply that it was just as splendid as any of the better known rooms, e.g the ballroom. The meaning is 2), that the room is on a par with the most splendid.
It does sound very old-fashioned though. Not incorrect but a bit flowery. The word splendid is used in UK English but depending on context it may sound a bit dated. A more modern way of saying the same thing would be ‘it was as impressive as any other room’ or if you really want to use the word splendid ‘it was as splendid as all the other rooms’.