Monero has just forked and is using new algorithm. Reason for changing it is that Monero network is infested with lots of ASICs and hopefully, after the fork, they will be gone. This means difficulty should drop a lot with time and profitability of mining should increase.
Unfortunately at the same time, they changed how their algorithm works and it caused 50% hashrate drop for everyone.
There are estimates that around 80% of Monero network is made out of ASICs so if they are true, 50% hashrate drop is not so bad and it should still be profitable to mine Monero. But we give no guarantees since those are all estimates.