No, in my opinion, altcoins can never be compared with Bitcoin. You can see the performance of the market. When bitcoin rises, altcoins fall. When bitcoin falls, altcoins are still falling.
But this does not mean that it will always be so. I think that some promising altcoins will be able to take some of his influence on the market from bitcoin.
I think that in a few years the market will change beyond recognition and we will have 5-10 very strong projects that will divide among themselves a large half of the market capitalization.