I dislike striker fired pistols and don't own any. The consensus among P365 owners is that the striker is fully cocked by the slide action. That makes it single action to me. Others say it is only partially cocked, like a Glock, but that's still not double action in my mind.
Sig's website avoids the debate by describing the trigger action as "striker fired."
As for safeties, the only Sigs that I know have external safeties are the single action only models, including the 1911.
The point of my original post is some “newer” pistols do not have an external safety unless required by state law. Almost all manufacturers offer at least one DAO model. Under stress all you do is squeeze the trigger, like a revolver.
I used to use a 1911 for home defense but purchased a DAO because if, under stress, I forgot the safety things could get bad quickly.
For people who have plenty of time and money to practice shooting with a safety, great. But if training is more limited because of budgets or time DAO is recommended (at least according to one of our local rangemasters).