i don't think centralized exchanges are going anywhere or even changing in the future. they may become more secure but that would be about it.
at the same time decentralized exchanges will grow but as an additional option that you can use if you wanted to go that rout and needed the decentralization. but there is still a lot of downsides to them for example you can not trade with fiat on a decentralized exchange, it still remains easier to use  centralized ones for that matter.