There are tubeless tires that are for hooked/crochet rims. So I'm not certain why the OP seems to pose that going to tubeless tires will require smooth bead or hookless rims.

And the word "safe" always gets thrown around in the mix. At the speed most cyclists ride, a tire rolling off the rim or burping air is just going to result in one having to come to a stop and address the issue. Not a automatic trip to the hospital.