Bitcoin mining is no longer a business that a sole miner can pursue and with the last halving, it is becoming difficult for small miners too. Only big companies are into Bitcoin mining which is a shame as it was never meant to be controlled by those who have money or you can say the corporates.
Now, it's almost impossible to mine bitcoin solo, but it's not that small miners are out of the business. Small miners can join mining pools.
The article you shared doesn't say anything about why blocks can take more than 10 minutes to be mined.