Not anymore than PoW, which requires specialized hardware that can't be repurposed for other uses (and thus requires money to enter). I'm not sure if is still true, but I believe at one point less than 10 companies had over 51% of the BTC network.

Because ownership tends to be much more evenly distributed than ACIS ownership, it makes it harder to collude - you have to have 51% of all coins that are staked (and smaller owners generally pool to stake as well). In addition, a move to collude would almost instantly destroy the value of the staked coin (though maybe not assets tokenized on it), providing another incentive against it.