The increased emphasis on Saftey would have happened anyway, although it may have taken 1 more fatal or near-fatal crash to complete the process. Dale Sr's death was the last in a series that included Adam Petty's (which may have had more long term-effect on NASCAR that Dale Sr's death). The real impact comes on Dale Sr's role, as he lives, as team owner and mentor to his son. Dale Sr was 49 and his career as a driver was waning. However, it is easy to imagine that if Dale Sr had survived, DEI would have assumed the position of superiority that Hendricks has gained and the beneficiary of this would be Dale Jr. Given more time to develop before becoming the racing head of family and racing in a team directed with incredible precision and dedication by his father, it is quite likely that Dale Jr would be five-time, not Darth Johnson. For a double POD, have Adam Petty live as well, therefore maintaining the spark of Petty Racing and giving Dale Jr the true rival he deserved.
BTW - I am not a member of Junior Nation, I did not like Dale Sr and I don't like Dale Jr, but had Sr lived to retire and build DEI into a powerhouse (and he would have) Jr would be the big winner. Like it or not.