Hubert lost his life after he was involved in a horrific accident on Saturday at the Circuit Spa-Francorchamps during the Formula 2 Feature Race.
The FIA is currently investigating the crash with the local Belgian authorities, while Juan Manuel Correa, who was also involved in the accident, is recovering from injuries to his legs and spine.
Stewart, who campaigned for driver safety while he competed through what is often cited as F1's most dangerous period, believes that the new generation is still new to the shock of losing a driver through a crash
"In my view, there have been far too many incidents over the last 24 or 36 months because there has never been a penalty to the extent we saw this weekend," the three-time world champion told PA.
"The drivers might now be prepared to recognise that they will have to take fewer liberties because you should never start thinking you are bulletproof.
"The shock and grief that was very evident in Spa is something that is new to this generation. Suddenly, everybody is aware that my God, if we do the wrong thing here, there is going to be a disaster. There hadn't been a disaster for such a long time.
"It is not impossible for another one to happen. Sometimes they come along in threes. We have seen that with aircraft accidents. It shakes everybody up. You cannot think you are going to get off with it all the time. This could be a wake-up call."
Stewart says he was with Senna's former teammate Alain Prost after the crash, admitting that it felt like they were "turning back the clock".
"I was with Alain just after the crash," Stewart said. "We spoke on the grid, too, and we were both very sad. It felt like 'play it again, Sam', and that we were turning back the clock.
"Things have moved on extremely well from my day where death was part and parcel of the business. If you didn't want to do it, if the kitchen was too hot, then you'd better get out.
"The number of drivers you see walk away from huge crashes are now ten-a-penny, and that is fantastic. But every now and then, the wrong accident occurs, and that is what happened here."
Bahrain International Circuit - Winter testing