Perhaps. I note your use of the plural "suits". If he can bring in clubs and spade losing either 1 spade and no clubs or 1 club and no spades then yep, a slam is there.
So otherwise put, 5
says "11 tricks for sure, absent some weird distribution, and 12 should be there if we can bring in the blacks with the loss of 1 trick".
One way to look at this: If we are going to be in slam on 30 highs we had better have some shape. Well, here we have shape, lots of shape, but the N shape and the S shape aren't working well together. So pessimism is warranted. Surely we do not want to play this in clubs, and if we play it in spades we might lose 0 or 1 or 2 spades and we will lose 1 club. Maybe the best shot would be 6
played by S since that eliminated the problem of a spade lead at T1, but there is no way to arrange that.
Some hands favor the optimists, some, like this one, favor the pessimists. Here they can ope 5
comes in. Maybe it does. Maybe not.