Miners don't only make money out of Block rewards (Block reward is the reward in BTC which currently is 6.25) but a miner makes money out of the fee that people pay while making transactions. Because miners are the ones who validate TX and process TX and spend their useful resources (machinery) and spend a huge amount of energy just to earn money.
The question would be, as the block reward diminishes, will the transaction fee make up for the reduced reward? If there is not enough transaction to compensate miners for the reduced reward and miners experienced shortage of profit, this would be a big problem on the Bitcoin ecosystem.
And with halving, there is no doubt that the block reward reduced to half, which of course a loss for the miners, but as you can see, with each halving, the price of BTC improved and the amount that miners were making in BTC did decreased but in fiat (USD) it increased. I hope there is no need to give an example.
This is the reason why adoption and Bitcoin integration to companies as mode of payment must sync with or even goes further with the halving to compensate for the reduced reward. Relying on the price increase alone is not sufficient because somewhere down the road price increase will meet its choke point and as the mining reward goes to zero, it will only rely on the transaction fee for the reward, reason why adoption and integration is very important.
So, I think when the halving in April occurs, the price of BTC will improve and reach to a height where it will be making them the same or more money even from the fee which from another point of view, might be a problem for the TXs makers. But it can be solved using the Lightning network.
I hope that the increase in price will make mining more than profitable because I think as of now tx fee reward cannot make up for the reduced reward due to halving.