The downforce fan technique was also done by Formula 1 in the late 70s before being banned the year after. https://en.wikipedia.org/wiki/Brabham_BT46#Brabham_BT46B_%E2...
There are all kinds of restrictions added to race cars of almost any series, some for commercial reasons (promoting the original vehicle in rallying and touring cars for example), some for financial (generally to keep the price of entry reasonable) and sometimes for safety.
Watching Travis Pastrana jump the fountains on a fairly heavy Indian flat track bike, with modern ramps designed with computer input, and planning rather than seat-of-the-pants go-for-it-ness made it okay, but hardly death-defying. I see guys jump motorcycles furthers on the dunes in Southern California. When EK did it, it was terrifying.
Just like F1 was, once upon a time. Now F1 is scary because speeds are up against human reaction. It's inevitable the cars either have to slow down, or the driver needs to be on controls not in the car, making this ground-based drones.
Just because all cars can get it easily doesn't mean F1 want it. Most often the quoted reason is to have a better spectator sport and to make it safer. I really doubt those reasons because you can still have a difficult and tight race while having all the modern safety features. For example why don't F1 cars have entire car air bags (ie air bags that envelop the entire car that deploy when the car goes airborne in a crash/rollover)? if it's too "heavy" just make a rule that all F1 cars need to have air bags so the playing field is even.
F1 cars should have self driving collision avoidance that can activate faster than human response times as well. that would be way safer for everyone involved.
He might have bounced off the guard rail or be stuck in it just the same with extra material surrounding him and catching fire.
There have been also at least two cases I remember of race cars becoming airborne after touching wheels and being able to continue the race. This usually happens when the field is packed after (re)starts. Deploying airbags in such cases would probably entail a chain reaction that might resemble corn being popped.
The last 10 years many of the F1 cars due to the rules had catastrophic loss of downforce if they got too near other cars. The drivers had to work around this by not following too closely. F1 rules changes recently have tried to reduce these kinds of issues.
But even this last season was somewhat ruined by one team figuring out to work within the current rules and not have the porpoising problems that wrecked the other teams cars because they'd lose their downforce. That made the racing less exciting. And the whole problem never had to exist if it wasn't for the rules.
But I don’t remember catastrophic loss of downforce as bad as this: https://youtu.be/e21ZjwZGjiQ
While the downforce loss was significant, it was predictable and could be easily avoided. The equivalent for ground effect, e.g. hitting a bump or curb mid-corner and lifting the skirt just far enough for the pressure seal to fail and your downforce to go from 100% to near 0% in an instant, is far more likely to lead to a catastrophic accident.
The air bags have been covered in other comments but similarly would probably reduce safety, not increase it. The cars are very much designed for safety, and to absorb impacts, which is why they are so much heavier than previous generations.
In fact there's almost no racing events that have a true open class engineering wise anymore. It's just too dangerous. Look up what happened during the Group B Rally era for examples of how it can go wrong and blow back.
The background to why Gordon Murray (designer) decided to go with the fan design was the flat-12 engine used by Brabham didn't allow venturi tunnels along the side of the car (flat-12s being too wide) so he had to find another way to respond to the then-new ground-effect others were exploiting.
A neat legal trick was discovered: a fan could be installed on the car as long as its primary purpose was to cool the motor. Primary purpose in this case meant, and GM got a lawyer's opinion on this, at least 51% of the volume of air went to cool the engine. Brabham was very clear this fan sucked the car to the ground but also proved to the governing body that most of the air went to cooling, so it was deemed legal for the rest of the year but the loophole was to be closed for the following year. Stories by Andretti about the BT46 throwing stones and being dangerous to other drivers was complete rubbish made up by Colin Chapman to get the car banned as he saw Brabham would walk away with the championship. In effect the tips of the fans never moved particularly fast (ballpark 50mph along the edges) so it was never dangerous to other drivers.
The actual story as to why it was withdrawn is Bernie Ecclestone, then owner of the Brabham team was also the head of the Formula One Constructors Association and the other manufacturers threatened to leave the association if he didn't withdraw the car. Seeing the bigger picture of securing TV and advertising rights to F1, Bernie withdrew the car after a single race.
"Although it was quickly banned, the 2J “vacuum cleaner” concept was copied eight years later by Brabham Formula 1 designer Gordon Murray who figured out a way to circumvent the rules." - Wikipedia
i have a '60s lotus 23, which was built for Le Mans, and it was very low six figures. but an engine rebuild is $30k...
Trackdays skew towards much more modern cars. Although I met the shop that takes care of my stuff at one (they did Spec Miata rental, and now I race that too)