Additionally, a grip safety may involve additional training. True. However, so does ANY feature on any pistol. Training on a feature to increase safety seems infinitely worthwhile.
Yes, but new shooters who have issues with grip or someone who has various hand issues or someone whose hands don't fit the gun may find a DA/SA trigger to be more reliable than a grip safety. Again, no one-size fits all.
1911s have grip safeties as well -- CZs do not, nor do many other Condition 1-capable guns... FWIW, b/c of this I'd consider the risk profile for 1911s to be more akin to Condition 2 than Condition 1 like we're talking about here. Effectively w/ 1911s you're 3 steps to fire -- deactivate safety, grip to deactivate grip safety, and then pull the trigger.
By comparison, Glock's have 1 step -- pull SA trigger and I'd don't consider their trigger blade/lever to count as an add'l safety step. Springfield XDs have 2 steps (grip safety or less common manual-only + SA trigger), CZs have 2 steps (either DA trigger pull or safety + SA trigger), etc.
Point being, 1911s are one of the safest cocked-and-locked carry options with a different risk profile than other models.
I agree that there's benefit to additional safety functions -- to each his own on whether the juice is worth the squeeze w/ additional safety measures... Personally, I greatly prefer at least 2 functions to fire. As I think I mentioned, there are instances where I carry a DA/SA pistol that's both decocked and w/ a manual safety on for varmint use -- but for social or self-defense against human use, I tend to believe that condition 2 on DA/SA guns without a manual safety is the best risk profile for me, and in this condition I don't want to carry guns with a manual safety when possible to prevent the possibility that the safety is activated should I need to use the firearm under duress... So if there's a manual safety, I just train around using it...
And if I were a woman and carrying a loaded pistol in a bag, then I'd probably also want a manual safety along with carrying it decocked as the additional time to deactivate would be minimal and every woman I know also has many moments where their purse is not in their hand or on their shoulder, so the additional safety provides benefit in the event an unauthorized party accesses their firearm. If children might be the unauthorized party, then a grip safety may also provide benefit in add'l risk mitigation... A woman carrying a firearm on her person would largely if not entirely have the same risk considerations as a man.
Which leads to my second point -- so long as folks have given serious thought to and understand the risks and benefits to their firearm's safety functions, then they should do what they will, but if folks are just following what others are doing, maybe give some more thought before starting down any course of action... For instance, there are many times where I could carry guns in Condition 1 without causing reliability issues, but again, to what extent can I standardize the manual of arms, does this fit my manual of arms standard... And if I were a competition shooter who has tens of thousands of reps w/ manual safeties, then I would error to the side of Condition 1 always -- but I'd probably look to a flap holster if I was doing stuff around a lot of sticks or mud where something may be able to work its way between hammer and firing pin and same "keep gun but make other changes" to address specific scenarios -- at least up and until the concessions are no longer are acceptable to you.
Hope this makes sense... Seems like a long and roundabout way to say -- think long and hard about a variety of common scenarios for you before you decide/purchase (don't just default to what others are doing), actually put your purchase/configuration through the paces (with an unloaded firearm when appropriate) to ensure it actually works for you as intended/expected in your daily life, and be willing to adapt your preferences to the necessities of your specific circumstances (wanting something to work and it actually working are two different things). And realize that as your seasons of life change, you must continue to re-evaluate whether your current situation is still optimal, and then actually do so.