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.