The statistics are staggering.
Only after 1982 did the frequency of fatal accidents decrease: two driver fatalities in 1994 (Roland Ratzenberger and Ayrton Senna, during the infamous Imola GP); three marshalls in 2000, 2001 and 2013; and Jules Bianchi, who died in 2015 from injuries sustained from a crash during the 2014 Japanese GP.
In later decades major changes to improve safety were carried out, which explains the decrease.
I'm a big fan of the sport. But looking at the place safety has in the way we think about sports today (from Motorsport to concussions in Boxing and American Football, for example) I wonder how did the sport survive for all those terrible years.
Weren't fans horrified? Wasn't the press scandalized? Weren't the drivers outraged? Is it all explained by a different mentality towards safety, or something more?
Part of it was due to different views on how safety should be regarded. From what I could tell, motorsport racing was one of the sports where it was accepted that a driver would and could die at any moments' notice.
Another part was that Formula One and motorsport racing alliances and associations were and are fairly conservative because the public perception of the sport and part of the spectacle were the rather intense crashes that happened every so often. I think fans were horrified for sure especially considering events like the 1955 Le Mans, the horrific 1957 Mille Miglia crash where Alfonso de Portago was found bisected after his crash in his Ferrarri 335.
Even earlier were the pre-war Formula 1 and motorsport deaths which all garnered quite a lot of negative attention, examples such as the 1903 Paris-Madrid race where it seems the multitude of accidents both drew the ire and wonder of the press and fans alike. Or the tragic death of Bernd Rosemeyer who died attempting to break a land speed record.
I think there certainly is a component of romance that came with motorsport that still has many people today complaining about innovations in safety. That said I don't think that people weren't cognizant or the press completely oblivious to the whole affair. Quite a few tracks over the decades of motorsport were closed due to the sheer dangers of them. Sid Watkins, one of the foremost Formula 1 doctors reckons that carbon fiber along with advances in medical imaging and treatment made huge strides in treating injuries that otherwise would have been fatal.
But within just Formula 1 itself, I reckon that as more and more drivers who found massive success met gruesome fates at the mercy of the tracks you started to see a backlash towards lackadasical or lax organization with regards to safety. I recall in Sid Watkins' Life at the Limit that early circuits essentially had zero marshal training and practically no medical facilities until constructors protested vehemently of the dangers their drivers faced.
Another factor to consider was that the heavily monetized and televised Formula 1 that we know today, was very much not so in the past. After WWII motorsport racing essentially had to be rebuilt from the ground up, having suffered through a massive economic turmoil during the post war time and a death by the onset of WWII itself. For the most part, both circuit managers and racing drivers themselves tended to have no large overarching organization until the 1970s, where even then conflicts between the Constructors Associations and smaller teams or the circuit managers continually occurred because modernizing for safety was both expensive and time consuming.
I'd wager that a part of the safety deficits were due to a confluence of a lack of medical knowledge, but also a tacit acceptance that automobiles were inherently dangerous things and driving fast even more dangerous. Remember that even in the civilian world, most safety innovations didn't occur until after the 1960s. Even though monstrous crashes happened with frightening regularity, the fatalities in Formula 1 were likely far easier to justify than the alarmingly high automobile fatalities that ran parallel to those decades.
As for the sport's survival, Formula One was never really that big until the early part of the 1970s. Much of its expansion amusingly coincided with the increase and proliferation of tobacco and corporate sponsorships that allowed smaller garagistes in the 60s to thrive and expand in the 70s. Even then, Formula 1 saw quite a large variety of rather...odd teams who vied for the crown. Combined with a decently cheap cost to entry thanks to the incredible Cosworth DFV and Hewland 5 Speed Manual Gearbox being practically ubiquitous, Formula One survived through a combination of having a variety of teams but also a surge of interest thanks to the resurgence of wealth that came with the 60s and 70s.
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