The Frenchman was unable to keep his Marussia car under control in the wet conditions in Suzuka earlier this month and subsequently collided with a recovery vehicle attending to Adrian Sutil's spin at the same corner.
Bianchi suffered serious head injuries, leading to his father Philippe this week describing the situation as "desperate", with the 25-year-old yet to regain consciousness some 10 days after the accident.
M-Sport rally driver Kubica, who previously competed in F1 with BMW Sauber and Renault, was involved in a serious crash at the 2007 Canadian Grand Prix. And, in the wake of Bianchi's troubles, he is adamant that the sport will never be completely safe.
He told BBC Sport: "When you see it, you ask how is this possible? But unfortunately, it can happen. There is always risk in motorsport.
"We can forget how motorsport can be dangerous. My case is not the same but I was quite unlucky and lucky - you can see it both ways. I wish Jules and his family all the best and I pray for him.
"I know him quite well, he's a really nice guy and his talent is high, but it doesn't matter how much talent he has or if he is a friend or not - the danger remains."